National Library of Energy BETA

Sample records for high heat flow

  1. Air flow in a high aspect ratio heat sink

    E-Print Network [OSTI]

    Allison, Jonathan Michael

    2010-01-01

    The increasing heat output of modern electronics requires concomitant advances in heat sinking technology: reductions in thermal resistance and required pumping power are necessary. This research covers the development of ...

  2. Film boiling of saturated liquid flowing upward through a heated tube : high vapor quality range

    E-Print Network [OSTI]

    Laverty, W. F.

    1964-01-01

    Film boiling of saturated liquid flowing upward through a uniformly heated tube has been studied for the case in which pure saturated liquid enters the tube and nearly saturated vapor is discharged. Since a previous study ...

  3. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  4. Radial flow heat exchanger

    DOE Patents [OSTI]

    Valenzuela, Javier (Hanover, NH)

    2001-01-01

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  5. Hydrodynamics, heat transfer and flow boiling instabilities in microchannels 

    E-Print Network [OSTI]

    Barber, Jacqueline Claire

    2010-01-01

    Boiling in microchannels is a very efficient mode of heat transfer with high heat and mass transfer coefficients achieved. Less pumping power is required for two-phase flows than for single-phase liquid flows to achieve ...

  6. Lithospheric Heat Flow and Dynamics! obvious signals!

    E-Print Network [OSTI]

    Sandwell, David T.

    · $d( ) heat = flow scalar subsidence rate constant X #12;heat flow related to subsidence rate (qb ! quLithospheric Heat Flow and Dynamics! ! · obvious signals! - heat flow, depth, and geoid height?! - are transform faults thermal contraction cracks?! #12;global heat budget! 7.5 TW 44 TW 25-15 TW 3-13 TW

  7. MODERN DEVELOPMENTS IN MULTIPHASE FLOW & HEAT TRANSFER

    E-Print Network [OSTI]

    Lahey, Richard T.

    MODERN DEVELOPMENTS IN MULTIPHASE FLOW & HEAT TRANSFER "ENGINEERING APPLICATIONS OF FRACTAL and multiphase flow & heat transfer will be stressed. This paper will begin by reviewing some important concepts

  8. Heat Transfer in Smooth and Ribbed Rectangular Two-Pass Channels with a Developing Flow Entrance at High Rotation Numbers 

    E-Print Network [OSTI]

    Huh, Michael

    2010-01-16

    regionally averaged heat transfer coefficient i designates a given region in the channel (1?i?12) I current k thermal conductivity of the coolant L length of the heated portion of the test section m mass flow rate Nu regionally averaged... 16 1:4 Smooth streamwise Nu ratio distributions at different Reynolds numbers................................................................................................... 45 17 1:4 Smooth streamwise Nu ratio distributions...

  9. Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal...

    Open Energy Info (EERE)

    Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas- Features And Examples Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article:...

  10. A Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow...

    Open Energy Info (EERE)

    A Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow Measurements And Heat-Flow Estimates From The Uk Geothermal Catalogue Jump to: navigation, search OpenEI Reference...

  11. Sabdia's Radial Flow Air Bearing Heat Exchanger

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

    Sandia's Radial Flow ir Bearing Heat Exchanger 2014 Building Technologies Office Peer Review Sandia's TRL 5 Air Bearing Heat exchanger technology (a. k. a. The Sandia Cooler)...

  12. Surface heat flow, crustal temperatures and mantle heat flow in the Proterozoic

    E-Print Network [OSTI]

    Rolandone, Frederique

    ) and an ancient island arc (Lynn Lake Belt) made of depleted juvenile rocks. Higher heat flow values foundSurface heat flow, crustal temperatures and mantle heat flow in the Proterozoic Trans-Hudson Orogen report on new measurements of heat flow and radiogenic heat production in 30 boreholes at 17 locations

  13. Turbine vanes experience high convective surface heat transfer as a consequence of the turbulent flow exiting the combustor. Before im-

    E-Print Network [OSTI]

    Thole, Karen A.

    1 Abstract Turbine vanes experience high convective surface heat transfer as a consequence region of the passage reacts as it passes between two adjacent turbine vanes. In this study, a scaled-up turbine vane geometry was used in a low-speed wind tunnel simulation. The test section included a cen

  14. Heat Transfer Characteristics of a Generalized Divided Flow Heat Exchanger 

    E-Print Network [OSTI]

    Singh, K. P.

    1979-01-01

    CHARACTERISTICS OF A GENERALIZED DIVIDED FLrnJ HEAT EXCHANGER KRISHNA P. SINGH, CHIEF ENGINEER JOSEPH OAT CORPORATION 2500 Broadway, Camden, New Jersey 08104 ,l\\bstract The concept of a "Di vi ded-fl O~I" heat exchanger is general i zed by 1oca t i n...-Pass Split-Flow Shell Trans. of the ASME, Journal of Heat Transfer, pp 408-416, Aug. 1964. (4) Singh, K. P. and Holtz, ~I.J., "Generalization of the Split Flow Heat Exchanger - Geometry for Enhanced Heat Transfer", 18th National ASME/AICHE Heat Transfer...

  15. Heat Pump for High School Heat Recovery 

    E-Print Network [OSTI]

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

    2006-01-01

    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...

  16. 4.A. HEAT FLOW 119 4.A. Heat flow

    E-Print Network [OSTI]

    Hunter, John K.

    denote the temperature, g : R the rate per unit volume at which heat sources create energy inside the body, and q : Rn the heat flux. That is, the rate per unit area at which heat energy diffuses across of energy implies that for any smooth open set the heat flux out of is equal to the rate at which heat

  17. The heat recovery steam generator (HRSG) is a key component of Combined Cycle Power Plants (CCPP). The exhaust (flue gas) from the CCPP gas turbine flows through the HRSG -this gas typically contains a high

    E-Print Network [OSTI]

    The heat recovery steam generator (HRSG) is a key component of Combined Cycle Power Plants (CCPP). The exhaust (flue gas) from the CCPP gas turbine flows through the HRSG - this gas typically contains a high

  18. Heat Flow Database Expansion for NGDS Data Development, Collection...

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

    Heat Flow Database Expansion for NGDS Data Development, Collection and Maintenance (SMU) Heat Flow Database Expansion for NGDS Data Development, Collection and Maintenance (SMU)...

  19. Colorado Heat Flow Data from IHFC

    SciTech Connect (OSTI)

    Zehner, Richard E.

    2012-02-01

    Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Originator: The International Heat Flow Commission (IHFC) Publication Date: 2012 Title: Colorado IHFC Data Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science (CIRES), University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: Abstract: This layer contains the heat flow sites and data of the State of Colorado compiled from the International Heat Flow Commission (IHFC) of the International Association of Seismology and Physics of the Earth's Interior (IASPEI) global heat flow database (www.heatflow.und.edu/index2.html). The data include different items: Item number, descriptive code, name of site, latitude and longitude, elevation, depth interval, number of temperature data, temperature gradient, number of conductivity measurement, average conductivity, number of heat generation measurements, average heat production, heat flow, number of individual sites, references, and date of publication. Spatial Domain: Extent: Top: 4522121.800672 m Left: 165356.134075 m Right: 621836.776246 m Bottom: 4097833.419676 m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude Of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System 1984 (WGS ’1984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shape file

  20. Heat Flow Database Expansion for NGDS Data Development, Collection...

    Open Energy Info (EERE)

    Heat Flow Database Expansion for NGDS Data Development, Collection and Maintenance Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Heat...

  1. Triaxial thermopile array geo-heat-flow sensor

    DOE Patents [OSTI]

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

    1990-01-01

    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.

  2. 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)

    1992-01-01

    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.

  3. DESIGN OF A COMPACT HEAT EXCHANGER FOR HEAT RECUPERATION FROM A HIGH TEMPERATURE ELECTROLYSIS SYSTEM

    SciTech Connect (OSTI)

    G. K. Housley; J.E. O'Brien; G.L. Hawkes

    2008-11-01

    Design details of a compact heat exchanger and supporting hardware for heat recuperation in a high-temperature electrolysis application are presented. The recuperative heat exchanger uses a vacuum-brazed plate-fin design and operates between 300 and 800°C. It includes corrugated inserts for enhancement of heat transfer coefficients and extended heat transfer surface area. Two recuperative heat exchangers are required per each four-stack electrolysis module. The heat exchangers are mated to a base manifold unit that distributes the inlet and outlet flows to and from the four electrolysis stacks. Results of heat exchanger design calculations and assembly details are also presented.

  4. Flow and heat transfer in vertical annuli

    SciTech Connect (OSTI)

    Ulke, A.; Goldberg, I.

    1993-11-01

    In shell-side boiling heat exchangers narrow crevices that are formed between the tubes and the tube support structure provide areas for local conditions which differ significantly from the bulk fluid conditions. A quasi-two-dimensional model which was developed to describe the local phenomena in a vertical, cylindrical crevice was described previously. The present work compares experimentally obtained flow and tube temperature distributions to those predicted by the model. The results confirm the characteristic ``W`` shape of the tube temperature profile centered at the line contact between a heated tube and tube support.

  5. Heat flow and microearthquake studies, Coso Geothermal Area,...

    Open Energy Info (EERE)

    Heat flow and microearthquake studies, Coso Geothermal Area, China Lake, California. Final report Jump to: navigation, search OpenEI Reference LibraryAdd to library Book: Heat flow...

  6. Heat flow studies, Coso Geothermal Area, China Lake, California...

    Open Energy Info (EERE)

    Heat flow studies, Coso Geothermal Area, China Lake, California. Technical report Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Heat flow studies, Coso...

  7. Joule heating at high latitudes

    SciTech Connect (OSTI)

    Foster, J.C.; St.-Maurice, J.; Abreu, V.J.

    1983-06-01

    High latitude Joule heating has been calculated from simultaneous observations of the electric field magnitude and the Pedersen conductivity calculated from individual measurements of the ion drift velocity and particle precipitation observed over the lifetime of the AE-C satellite. The data were sorted by latitude, local time, hemisphere, season, and Kp index and separate averages of the electric field magnitude, Pedersen conductivity and Joule heating was prepared. Conductivities produced by an averaged seasonal solar illumination were included with those calculated from the particle precipitation. We found that high-latitude Joule heating occurs in a roughly oval pattern and consists of three distinct heating regions: the dayside cleft, the region of sunward convection at dawn and dusk, and the midnight sector. On the average, heating in the cleft and dawn-dusk regions contributes the largest heat input. There is no apparent difference between hemispheres for similar seasons. Hemisphere averaged Joule heating at equinox amounts to approximately 25 GW for Kp = 1 conditions, 85G GW for Kp = 4, and varies linearly as a function of Kp. The Joule heat input is 50% greater during the summer than during winter primarily due to the increased conductivity caused by solar production.

  8. Hamiltonian Thermostats Fail to Promote Heat Flow

    E-Print Network [OSTI]

    Wm. G. Hoover; Carol G. Hoover

    2013-07-16

    Hamiltonian mechanics can be used to constrain temperature simultaneously with energy. We illustrate the interesting situations that develop when two different temperatures are imposed within a composite Hamiltonian system. The model systems we treat are "phi-4" chains, with quartic tethers and quadratic nearest-neighbor Hooke's-law interactions. This model is known to satisfy Fourier's law. Our prototypical problem sandwiches a Newtonian subsystem between hot and cold Hamiltonian reservoir regions. We have characterized four different Hamiltonian reservoir types. There is no tendency for any of these two-temperature Hamiltonian simulations to transfer heat from the hot to the cold degrees of freedom. Evidently steady heat flow simulations require energy sources and sinks, and are therefore incompatible with Hamiltonian mechanics.

  9. Hydrodynamics and heat transfer during flow boiling instabilities in a single microchannel

    E-Print Network [OSTI]

    Aussillous, Pascale

    Hydrodynamics and heat transfer during flow boiling instabilities in a single microchannel July 2008 Keywords: Boiling Microchannels Visualisation Flow boiling instabilities Heat transfer a b intensification heat removal. Flow boiling heat transfer in microchannel geometry and the associated flow

  10. Development of a fuel-rod simulator and small-diameter thermocouples for high-temperature, high-heat-flux tests in the Gas-Cooled Fast Reactor Core Flow Test Loop

    SciTech Connect (OSTI)

    McCulloch, R.W.; MacPherson, R.E.

    1983-03-01

    The Core Flow Test Loop was constructed to perform many of the safety, core design, and mechanical interaction tests in support of the Gas-Cooled Fast Reactor (GCFR) using electrically heated fuel rod simulators (FRSs). Operation includes many off-normal or postulated accident sequences including transient, high-power, and high-temperature operation. The FRS was developed to survive: (1) hundreds of hours of operation at 200 W/cm/sup 2/, 1000/sup 0/C cladding temperature, and (2) 40 h at 40 W/cm/sup 2/, 1200/sup 0/C cladding temperature. Six 0.5-mm type K sheathed thermocouples were placed inside the FRS cladding to measure steady-state and transient temperatures through clad melting at 1370/sup 0/C.

  11. Geothermal Heat Pumps are Scoring High Marks

    SciTech Connect (OSTI)

    2000-08-01

    Geothermal Energy Program Office of Geothermal and Wind Technologies Geothermal Heat Pumps are Scoring High Marks Geothermal heat pumps, one of the clean energy technology stars Geothermal heat pumps (GHPs) are one of the most cost-effective heating, cooling, and water heating systems available for both residential and commercial buildings. GHPs extract heat from the ground during the heating season and discharge waste heat to the ground during the cooling season. The U.S. Environmental Protecti

  12. Heat Flow Determinations and Implied Thermal Regime of the Coso...

    Open Energy Info (EERE)

    Heat Flow Determinations and Implied Thermal Regime of the Coso Geothermal Area California Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Heat...

  13. Heat transfer and pressure drop in tape generated swirl flow

    E-Print Network [OSTI]

    Lopina, Robert F.

    1967-01-01

    The heat transfer and pressure drop characteristics of water in tape generated swirl flow were investigated. The test sections were electrically heated small diameter nickel tubes with tight fitting full length Inconel ...

  14. Numerical analysis of vapor flow in a micro heat pipe 

    E-Print Network [OSTI]

    Liu, Xiaoqin

    1996-01-01

    The vapor flow in a flat plate micro heat pipe with both uniform and linear heat flux boundary conditions has been numerically analyzed. For both types of boundary conditions, the Navier-Stokes equations with steady incompressible two...

  15. Heat exchanger with transpired, highly porous fins

    DOE Patents [OSTI]

    Kutscher, Charles F. (Golden, CO); Gawlik, Keith (Boulder, CO)

    2002-01-01

    The heat exchanger includes a fin and tube assembly with increased heat transfer surface area positioned within a hollow chamber of a housing to provide effective heat transfer between a gas flowing within the hollow chamber and a fluid flowing in the fin and tube assembly. A fan is included to force a gas, such as air, to flow through the hollow chamber and through the fin and tube assembly. The fin and tube assembly comprises fluid conduits to direct the fluid through the heat exchanger, to prevent mixing with the gas, and to provide a heat transfer surface or pathway between the fluid and the gas. A heat transfer element is provided in the fin and tube assembly to provide extended heat transfer surfaces for the fluid conduits. The heat transfer element is corrugated to form fins between alternating ridges and grooves that define flow channels for directing the gas flow. The fins are fabricated from a thin, heat conductive material containing numerous orifices or pores for transpiring the gas out of the flow channel. The grooves are closed or only partially open so that all or substantially all of the gas is transpired through the fins so that heat is exchanged on the front and back surfaces of the fins and also within the interior of the orifices, thereby significantly increasing the available the heat transfer surface of the heat exchanger. The transpired fins also increase heat transfer effectiveness of the heat exchanger by increasing the heat transfer coefficient by disrupting boundary layer development on the fins and by establishing other beneficial gas flow patterns, all at desirable pressure drops.

  16. DEVELOPING FLOW AND HEAT TRANSFER IN STRONGLY CURVED DUCTS OF RECTANGULAR CROSS-SECTION

    E-Print Network [OSTI]

    Yee, G.

    2010-01-01

    DEVELOpiNG FLOW AND HEAT TRANSFER IN STRONGLY CURVED DUCTS9092 Developing Flow and Heat Transfer in Strongly CurvedForced Convection Heat Transfer in Curved Rectangular

  17. Heat flow determinations and implied thermal regime of the Coso...

    Open Energy Info (EERE)

    Heat flow determinations and implied thermal regime of the Coso geothermal area, California Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  18. Model of critical heat flux in subcooled flow boiling

    E-Print Network [OSTI]

    Fiori, Mario P.

    1968-01-01

    The physical phenomenon occurring before and at the critical heat flux (CHF) for subcooled flow boiling has been investigated. The first phase of this study established the basic nature of the flow structure at CHF. A ...

  19. Pribnow, Kinoshita & Stein -1 -ODP Heat Flow Report Daniel Pribnow

    E-Print Network [OSTI]

    , Kinoshita & Stein - 4 - ODP Heat Flow Report Abstract. In this report the geothermal measurements made CD. 1. Introduction Geothermal measurements are important data needed to study the Earth's processes is essentially vertical and conductive, then heat flow can be calculated using Fourier's Law. In this case

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

    E-Print Network [OSTI]

    Kendall, Gail E.

    1978-01-01

    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 ...

  1. Applications of the Strong Heat Transformation by Pulse Flow in the Shell and Tube Heat Exchanger 

    E-Print Network [OSTI]

    Chen, Y.; Zhao, J.

    2006-01-01

    This article deals with the heat exchange coefficient varied with pulse frequency in the pulsation tube with different flow forms. The findings show that heat can be exchanged coefficient with the pulse frequency, and it ...

  2. 16 Heat Transfer and Air Flow in a Domestic Refrigerator

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    445 16 Heat Transfer and Air Flow in a Domestic Refrigerator Onrawee Laguerre UMR Génie Industriel........................................................................447 16.2.2 Heat Transfer and Airflow Near a Vertical Plate..................................................448 16.2.3 Heat Transfer and Airflow in Empty Closed Cavity

  3. Experiments on transformation thermodynamics: Molding the flow of heat

    E-Print Network [OSTI]

    Schittny, Robert; Guenneau, Sebastien; Wegener, Martin

    2012-01-01

    It has recently been shown theoretically that the time-dependent heat conduction equation is form-invariant under curvilinear coordinate transformations. Thus, in analogy to transformation optics, fictitious transformed space can be mapped onto (meta-)materials with spatially inhomogeneous and anisotropic heat-conductivity tensors in the laboratory space. On this basis, we design, fabricate, and characterize a micro-structured thermal cloak that molds the flow of heat around an object in a metal plate. This allows for transient protection of the object from heating, while maintaining the same downstream heat flow as without object and cloak.

  4. Mixed convection heat transfer to and from a horizontal cylinder in cross-flow with heating from below.

    SciTech Connect (OSTI)

    Greif, Ralph (University of California, Berkeley, CA); Evans, Gregory Herbert; Kearney, Sean Patrick (Sandia National Laboratories, Albuquerque, NM); Laskowski, Gregory Michael

    2006-02-01

    Heat transfer to and from a circular cylinder in a cross-flow of water at low Reynolds number was studied both experimentally and numerically. The experiments were carried out in a high aspect ratio water channel. The test section inflow temperature and velocity, channel lower surface temperature and cylinder surface temperature were controlled to yield either laminar or turbulent flow for a desired Richardson number. When the lower surface was unheated, the temperatures of the lower surface and water upstream of the cylinder were maintained approximately equal and the flow was laminar. When the lower surface was heated, turbulence intensities as high as 20% were measured several cylinder diameters upstream of the cylinder due to turbulent thermal plumes produced by heating the lower surface. Variable property, two-dimensional simulations were undertaken using a variant of the u{sup 2}-f turbulence model with buoyancy production of turbulence accounted for by a simple gradient diffusion model. Predicted and measured heat flux distributions around the cylinder are compared for values of the Richardson number, Gr{sub d}/Re{sub d}{sup 2} from 0.3 to 9.3. For laminar flow, the predicted and measured heat flux results agreed to within the experimental uncertainty. When the lower surface was heated, and the flow was turbulent, there was qualitative agreement between predicted and measured heat flux distributions around the cylinder. However the predicted spatially averaged Nusselt number was from 37% to 53% larger than the measured spatially averaged Nusselt number. Additionally, spatially averaged Nusselt numbers are compared to correlations in the literature for mixed convection heat transfer to/from cylinders in cross-flow. The results presented here are larger than the correlation values. This is believed to be due to the effects of buoyancy-induced turbulence resulting from heating the lower surface and the proximity of the cylinder to that surface.

  5. Effect of Inhomogeneity and Unsteadiness on the Stability of High-Speed Shear Flows 

    E-Print Network [OSTI]

    Bertsch, Rebecca Lynne

    2014-07-09

    In hypersonic flows, turbulence critically influences mass and momentum transport, mixing, heat transfer and acoustic noise generation. In contrast to incompressible flow, in high speed flows pressure is a true thermodynamic variable...

  6. Investigation of Groundwater Flow in Foothill and Mountain regions using Heat Flow measurements

    E-Print Network [OSTI]

    Fogg, Graham E.; Trask, James C

    2009-01-01

    Flow in Foothill and Mountain regions using Heat Flowenergy balance near mountain-front Finite element numericalcross-section for areal mountain-slope flow 10.2 2D cross-

  7. Flow visualization study of inverted annular flow of post dryout heat transfer region. [PWR; BWR

    SciTech Connect (OSTI)

    Ishii, M.; De Jarlais, G.

    1985-01-01

    The inverted annular flow is important in the area of LWR accident analysis in terms of the maximum cladding temperature and effectiveness of the emergency core cooling. However, the inverted annular flow thermal-hydraulics is not well understood due to its special heat transfer condition of film boiling. The review of existing data indicates further research is needed in the areas of basic hydrodynamics related to liquid core disintegration mechanisms, slug and droplet formation, entrainment, and droplet size distributions. In view of this, the inverted flow is studied in detail experimentally. A new experimental apparatus has been constructed in which film boiling heat transfer can be established in a transparent test section. The test section consists of two coaxial quartz tubes. The annular gap between these two tubes is filled with a hot, clear fluid (syltherm 800) so as to maintain film boiling temperatures and heat transfer rates at the inner quartz tube wall. Data on liquid core stability, core break-up mechanism, and dispersed-core liquid slug and droplet sizes are obtained using F 113 as a test fluid. Both high speed movies and flash photographs (3 ..mu..sec) are used.

  8. Geothermal Resource-Reservoir Investigations Based On Heat Flow...

    Open Energy Info (EERE)

    Geothermal Resource-Reservoir Investigations Based On Heat Flow And Thermal Gradient Data For The United States Jump to: navigation, search OpenEI Reference LibraryAdd to library...

  9. Temperatures, heat flow, and water chemistry from drill holes...

    Open Energy Info (EERE)

    Temperatures, heat flow, and water chemistry from drill holes in the Raft River geothermal system, Cassia County, Idaho Jump to: navigation, search OpenEI Reference LibraryAdd to...

  10. Enhanced two phase flow in heat transfer systems

    DOE Patents [OSTI]

    Tegrotenhuis, Ward E; Humble, Paul H; Lavender, Curt A; Caldwell, Dustin D

    2013-12-03

    A family of structures and designs for use in devices such as heat exchangers so as to allow for enhanced performance in heat exchangers smaller and lighter weight than other existing devices. These structures provide flow paths for liquid and vapor and are generally open. In some embodiments of the invention, these structures can also provide secondary heat transfer as well. In an evaporate heat exchanger, the inclusion of these structures and devices enhance the heat transfer coefficient of the evaporation phase change process with comparable or lower pressure drop.

  11. Heat flux carried by the Antarctic Circumpolar Current mean flow

    E-Print Network [OSTI]

    Rhode Island, University of

    Heat flux carried by the Antarctic Circumpolar Current mean flow Che Sun Geophysical Fluid Dynamics Graduate School of Oceanography, University of Rhode Island, Narragansett, Rhode Island, USA Received 18 of historical hydrographic data is applied to study the heat flux problem in the Antarctic Circumpolar Current

  12. Polymer Effects on Heat Transport in Laminar Boundary Layer Flow

    E-Print Network [OSTI]

    Roberto Benzi; Emily S. C. Ching; Vivien W. S. Chu

    2011-04-27

    We consider a laminar Blasius boundary-layer flow above a slightly heated horizontal plate and study the effect of polymer additives on the heat transport. We show that the action of the polymers can be understood as a space-dependent effective viscosity that first increases from the zero-shear value then decreases exponentially back to the zero-shear value as one moves away from the boundary. We find that with such an effective viscosity, both the horizontal and vertical velocities near the plate are decreased thus leading to an increase in the friction drag and a decrease in the heat transport in the flow.

  13. 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...

  14. Control of reactor coolant flow path during reactor decay heat removal

    DOE Patents [OSTI]

    Hunsbedt, Anstein N. (Los Gatos, CA)

    1988-01-01

    An improved reactor vessel auxiliary cooling system for a sodium cooled nuclear reactor is disclosed. The sodium cooled nuclear reactor is of the type having a reactor vessel liner separating the reactor hot pool on the upstream side of an intermediate heat exchanger and the reactor cold pool on the downstream side of the intermediate heat exchanger. The improvement includes a flow path across the reactor vessel liner flow gap which dissipates core heat across the reactor vessel and containment vessel responsive to a casualty including the loss of normal heat removal paths and associated shutdown of the main coolant liquid sodium pumps. In normal operation, the reactor vessel cold pool is inlet to the suction side of coolant liquid sodium pumps, these pumps being of the electromagnetic variety. The pumps discharge through the core into the reactor hot pool and then through an intermediate heat exchanger where the heat generated in the reactor core is discharged. Upon outlet from the heat exchanger, the sodium is returned to the reactor cold pool. The improvement includes placing a jet pump across the reactor vessel liner flow gap, pumping a small flow of liquid sodium from the lower pressure cold pool into the hot pool. The jet pump has a small high pressure driving stream diverted from the high pressure side of the reactor pumps. During normal operation, the jet pumps supplement the normal reactor pressure differential from the lower pressure cold pool to the hot pool. Upon the occurrence of a casualty involving loss of coolant pump pressure, and immediate cooling circuit is established by the back flow of sodium through the jet pumps from the reactor vessel hot pool to the reactor vessel cold pool. The cooling circuit includes flow into the reactor vessel liner flow gap immediate the reactor vessel wall and containment vessel where optimum and immediate discharge of residual reactor heat occurs.

  15. Boiling heat transfer in a vertical microchannel: Local estimation during flow boiling with a non intrusive method

    E-Print Network [OSTI]

    Boiling heat transfer in a vertical microchannel: Local estimation during flow boiling with a non the results of experimental and numerical studies concerning boiling heat transfer inside vertical in minichannels for several gravity levels (µg, 1g, 2g). To fully understand the high heat transfer potential

  16. Brine flow in heated geologic salt.

    SciTech Connect (OSTI)

    Kuhlman, Kristopher L.; Malama, Bwalya

    2013-03-01

    This report is a summary of the physical processes, primary governing equations, solution approaches, and historic testing related to brine migration in geologic salt. Although most information presented in this report is not new, we synthesize a large amount of material scattered across dozens of laboratory reports, journal papers, conference proceedings, and textbooks. We present a mathematical description of the governing brine flow mechanisms in geologic salt. We outline the general coupled thermal, multi-phase hydrologic, and mechanical processes. We derive these processes' governing equations, which can be used to predict brine flow. These equations are valid under a wide variety of conditions applicable to radioactive waste disposal in rooms and boreholes excavated into geologic salt.

  17. Enhanced flow boiling heat transfer in microchannels with structured surfaces at varied mass flow rates

    E-Print Network [OSTI]

    Bian, David (David Wei)

    2015-01-01

    This thesis investigates the role of mass flux on flow boiling heat transfer in microchannels with surface micropillar arrays. The motivation for this investigation was to determine the general trends of the optimal ...

  18. Friction-Induced Fluid Heating in Nanoscale Helium Flows

    SciTech Connect (OSTI)

    Li Zhigang [Department of Mechanical Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

    2010-05-21

    We investigate the mechanism of friction-induced fluid heating in nanoconfinements. Molecular dynamics simulations are used to study the temperature variations of liquid helium in nanoscale Poiseuille flows. It is found that the fluid heating is dominated by different sources of friction as the external driving force is changed. For small external force, the fluid heating is mainly caused by the internal viscous friction in the fluid. When the external force is large and causes fluid slip at the surfaces of channel walls, the friction at the fluid-solid interface dominates over the internal friction in the fluid and is the major contribution to fluid heating. An asymmetric temperature gradient in the fluid is developed in the case of nonidentical walls and the general temperature gradient may change sign as the dominant heating factor changes from internal to interfacial friction with increasing external force.

  19. Supersonic combustion of a transverse injected H sub 2 jet in a radio frequency heated flow

    SciTech Connect (OSTI)

    Wantuck, P.J.; Tennant, R.A.; Watanabe, H.H.

    1991-01-01

    The combustion of a single hydrogen jet, normally injected into a radio frequency (RF) heated, oxidant-containing, supersonic flow, has been established to characterize the chemical and fluid dynamic phenomena associated with the reaction process and ultimately validate the predictive capability of computational computer dynamic (CFD) codes. The experimental system employed for this study is unique in that it uses an electrodeless, inductively coupled plasma tube to generate the high temperature oxidant-containing gas for subsequent nozzle expansion. Advantages of an RF heated flow system include reduced free-stream chemical contamination, continuous operation, and relative ease of integration into a typical flow laboratory environment. A description of the system utilized for this study is presented including preliminary results of the reactive flow characterization. In addition, the use of the laser-based diagnostic techniques, such as planar laser-induced fluorescence (PLIF), for measuring flow properties is also discussed. 8 refs., 7 figs.

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

    SciTech Connect (OSTI)

    Mishima, K.; Ishii, M.

    1982-03-01

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

  1. PYROLYSIS OF METHANE IN A SUPERSONIC, ARC-HEATED FLOW

    E-Print Network [OSTI]

    Texas at Arlington, University of

    1 PYROLYSIS OF METHANE IN A SUPERSONIC, ARC-HEATED FLOW F.K. Lu,* C.M. Roseberry, J.M. Meyers and D arc pyrolysis of methane at supersonic conditions, representative of conditions in the reformer location of an aibreathing hypersonic vehicle. The rationale for arc pyrolysis is provided. Major

  2. INTERNAL FORCED iquid or gas flow through pipes or ducts is commonly used in heating and

    E-Print Network [OSTI]

    Ghajar, Afshin J.

    to flow by a fan or pump through a flow section that is sufficiently long to accomplish the desired heat Transitional Flow in Tubes* An important design problem in industrial heat exchangers arises when flow inside or ducts is commonly used in heating and cooling applications. The fluid in such applications is forced

  3. Classical and Quantum Chaos and Control of Heat Flow

    E-Print Network [OSTI]

    Giulio Casati; Carlos Mejia-Monasterio

    2006-10-10

    We discuss the problem of heat conduction in classical and quantum low dimensional systems from a microscopic point of view. At the classical level we provide convincing numerical evidence for the validity of Fourier law of heat conduction in linear mixing systems, i.e. in systems without exponential instability. At the quantum level, where motion is characterized by the lack of exponential dynamical instability, we show that the validity of Fourier law is in direct relation with the onset of quantum chaos. We then study the phenomenon of thermal rectification and briefly discuss the different types of microscopic mechanisms that lead to the rectification of heat flow. The control of heat conduction by nonlinearity opens the possibility to propose new devices such as a thermal rectifier.

  4. Heat transfer and pressure drop of supercritical carbon dioxide flowing in several printed circuit heat exchanger channel patterns

    SciTech Connect (OSTI)

    Carlson, M. [Univ. of Wisconsin - Madison, 839 Engineering Research Building, 1500 Engineering Drive, Madison, WI 53706 (United States); Kruizenga, A. [Sandia National Laboratory (United States); Anderson, M.; Corradini, M. [Univ. of Wisconsin - Madison, 839 Engineering Research Building, 1500 Engineering Drive, Madison, WI 53706 (United States)

    2012-07-01

    Closed-loop Brayton cycles using supercritical carbon dioxide (SCO{sub 2}) show potential for use in high-temperature power generation applications including High Temperature Gas Reactors (HTGR) and Sodium-Cooled Fast Reactors (SFR). Compared to Rankine cycles SCO{sub 2} Brayton cycles offer similar or improved efficiency and the potential for decreased capital costs due to a reduction in equipment size and complexity. Compact printed-circuit heat exchangers (PCHE) are being considered as part of several SCO{sub 2} Brayton designs to further reduce equipment size with increased energy density. Several designs plan to use a gas cooler operating near the pseudo-critical point of carbon dioxide to benefit from large variations in thermophysical properties, but further work is needed to validate correlations for heat transfer and pressure-drop characteristics of SCO{sub 2} flows in candidate PCHE channel designs for a variety of operating conditions. This paper presents work on experimental measurements of the heat transfer and pressure drop behavior of miniature channels using carbon dioxide at supercritical pressure. Results from several plate geometries tested in horizontal cooling-mode flow are presented, including a straight semi-circular channel, zigzag channel with a bend angle of 80 degrees, and a channel with a staggered array of extruded airfoil pillars modeled after a NACA 0020 airfoil with an 8.1 mm chord length facing into the flow. Heat transfer coefficients and bulk temperatures are calculated from measured local wall temperatures and local heat fluxes. The experimental results are compared to several methods for estimating the friction factor and Nusselt number of cooling-mode flows at supercritical pressures in millimeter-scale channels. (authors)

  5. EFFECT OF HORIZONTALLY INHOMOGENEOUS HEATING ON FLOW AND MAGNETIC FIELD IN THE CHROMOSPHERE OF THE SUN

    SciTech Connect (OSTI)

    Song, P.; Vasyli?nas, V. M.

    2014-12-01

    The solar chromosphere is heated by damped Alfvén waves propagating upward from the photosphere at a rate that depends on magnetic field strength, producing enhanced heating at low altitudes in the extended weak-field regions (where the additional heating accounts for the radiative losses) between the boundaries of the chromospheric network as well as enhanced heating per particle at higher altitudes in strong magnetic field regions of the network. The resulting inhomogeneous radiation and temperature distribution produces bulk flows, which in turn affect the configuration of the magnetic field. The basic flow pattern is circulation on the spatial scale of a supergranule, with upward flow in the strong-field region; this is a mirror image in the upper chromosphere of photospheric/subphotospheric convection widely associated with the formation of the strong network field. There are significant differences between the neutral and the ionized components of the weakly ionized medium: neutral flow streamlines can form closed cells, whereas plasma is largely constrained to flow along the magnetic field. Stresses associated with this differential flow may explain why the canopy/funnel structures of the network magnetic field have a greater horizontal extent and are relatively more homogeneous at high altitudes than is expected from simple current-free models.

  6. Buoyancy-driven heat transfer and flow between a wetted heat source and an isothermal cube

    SciTech Connect (OSTI)

    Close, D.J.; Peck, M.K.; White, R.F.; Mahoney, K.J. )

    1991-05-01

    This paper describes flow visualization and heat transfer experiments conducted with a heat source inside an isothermal cube filled with a saturated or near-saturated gas/vapor mixture. The mixture was formed by vaporizing liquid from the surface of the heat source, and allowing it to condense on the surfaces of the cube, which was initially filled with a noncondensing gas. Visualization studies showed that for air and ethanol below 35C, and for air and water, the flow patterns were similar with the hot plume rising from the source. For air and ethanol above 35C the flow pattern reversed with the hot plume flowing downward. For temperatures spanning 35C, which is the zero buoyancy temperature for the ethanol/water azeotrope and air, no distinct pattern was observed. Using water, liquid droplets fell like rain throughout the cube. Using ethanol, a fog of droplets moved with the fluid flow. Heat transfer experiments were made with water and air, and conductances between plate and cube of around 580 W{center dot}m{sup {minus}2}{center dot}K{sup {minus}1} measured. Agreement between the similarity theory developed for saturated gas/vapor mixtures, and correlations for single component fluids only, was very good. Together with qualitative support from the visualization experiments, the theory developed in a earlier paper deriving a similarity relationship between single fluids and gas/vapor mixtures has been validated.

  7. New flow boiling heat transfer model for hydrocarbons evaporating inside horizontal tubes

    SciTech Connect (OSTI)

    Chen, G. F.; Gong, M. Q.; Wu, J. F.; Zou, X.; Wang, S.

    2014-01-29

    Hydrocarbons have high thermodynamic performances, belong to the group of natural refrigerants, and they are the main components in mixture Joule-Thomson low temperature refrigerators (MJTR). New evaluations of nucleate boiling contribution and nucleate boiling suppression factor in flow boiling heat transfer have been proposed for hydrocarbons. A forced convection heat transfer enhancement factor correlation incorporating liquid velocity has also been proposed. In addition, the comparisons of the new model and other classic models were made to evaluate its accuracy in heat transfer prediction.

  8. A Site-Scale Model For Fluid And Heat Flow In The Unsaturated...

    Open Energy Info (EERE)

    multicomponent fluid and heat flow through porous and fractured rock. Fracture and matrix flow is treated using both dual-permeability and effective-continuum modeling...

  9. Time-resolved heat transfer in the oscillating turbulent flow of a pulse-combustor tail pipe

    SciTech Connect (OSTI)

    Dec, J.E.

    1988-01-01

    The need for efficient combustion systems has led to active research in pulse combustion. One advantage of pulse combustor heating systems is a high rate of heat transfer in the tail pipe. These high heat transfer rates result from large velocity oscillations, which occur in the tailpipe as a result of the acoustic resonance of the pulse combustor. Past research on the effects of flow oscillations on heat transfer rates is inconclusive; however, some oscillating turbulent flows have been shown to have Nusselt numbers, which are much higher than those to steady turbulent flow at the same mean Reynolds number. An experimental study of the heat transfer rates and convective transport processes in a pulse combustor tail pipe was conducted. A test combustor was used, in which the oscillation frequencies could be varied from 54 to 101 Hz, with peak-to-peak velocity oscillations from zero (steady flow) to 10 times the mean velocity, and mean Reynolds numbers from 3100 to 4750. Nusselt numbers in the tail pipe are enhanced by the oscillations up to a factor of 2.5 times the expected value for steady turbulent flow. The Nusselt number enhancement increases with both oscillation frequency and velocity oscillation amplitude. Increases in the mean Reynolds number decreased the enhancement. Possible causes for the heat-transfer enhancement in oscillating flows are discussed. The data indicate that the heat transfer enhancement results from a combination of increased turbulence intensity and transverse flows generated during the streamwise velocity reversals.

  10. 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

    2012-01-01

    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 ...

  11. Heat Flow From Four New Research Drill Holes In The Western Cascades...

    Open Energy Info (EERE)

    Heat Flow From Four New Research Drill Holes In The Western Cascades, Oregon, Usa Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Heat Flow From...

  12. Cedarville Elementary & High School Space Heating Low Temperature...

    Open Energy Info (EERE)

    Cedarville Elementary & High School Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Cedarville Elementary & High School Space Heating Low...

  13. Modular Low Cost High Energy Exhaust Heat Thermoelectric Generator...

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

    Low Cost High Energy Exhaust Heat Thermoelectric Generator with Closed-Loop Exhaust By-Pass System Modular Low Cost High Energy Exhaust Heat Thermoelectric Generator with...

  14. High Efficiency Microturbine with Integral Heat Recovery - Presentatio...

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

    High Efficiency Microturbine with Integral Heat Recovery - Presentation by Capstone Turbine Corporation, June 2011 High Efficiency Microturbine with Integral Heat Recovery -...

  15. High Efficiency Microturbine with Integral Heat Recovery - Fact...

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

    High Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 High Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 Capstone Turbine...

  16. High Operating Temperature Heat Transfer Fluids for Solar Thermal...

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

    High Operating Temperature Heat Transfer Fluids for Solar Thermal Power Generation FY13 Q1 High Operating Temperature Heat Transfer Fluids for Solar Thermal Power Generation FY13...

  17. High pressure ceramic heat exchanger

    DOE Patents [OSTI]

    Harkins, B.D.; Ward, M.E.

    1998-09-22

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 5 figs.

  18. High pressure ceramic heat exchanger

    DOE Patents [OSTI]

    Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)

    1998-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  19. High pressure ceramic heat exchanger

    DOE Patents [OSTI]

    Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)

    1999-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the reinforcing member and having a strengthening member wrapped around the refractory material. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  20. Heat transport by laminar boundary layer flow with polymers

    E-Print Network [OSTI]

    Roberto Benzi; Emily S. C. Ching.; Vivien W. S. Chu

    2011-04-23

    Motivated by recent experimental observations, we consider a steady-state Prandtl-Blasius boundary layer flow with polymers above a slightly heated horizontal plate and study how the heat transport might be affected by the polymers. We discuss how a set of equations can be derived for the problem and how these equations can be solved numerically by an iterative scheme. By carrying out such a scheme, we find that the effect of the polymers is equivalent to producing a space-dependent effective viscosity that first increases from the zero-shear value at the plate then decreases rapidly back to the zero-shear value far from the plate. We further show that such an effective viscosity leads to an enhancement in the drag, which in turn leads to a reduction in heat transport.

  1. Numeric Simulation of Heat Transfer and Electrokinetic Flow in an Electroosmosis-Based

    E-Print Network [OSTI]

    Le Roy, Robert J.

    Numeric Simulation of Heat Transfer and Electrokinetic Flow in an Electroosmosis-Based Continuous is dedicated to under- standing the fluid flow and heat transfer mechanisms occurring in continuous flow PCR are discussed in detail. The importance of each heat transfer mechanism for different situations is also

  2. FliHy experimental facilities for studying open channel turbulent flows and heat transfer

    E-Print Network [OSTI]

    Abdou, Mohamed

    FliHy experimental facilities for studying open channel turbulent flows and heat transfer B. Freeze) facility was constructed at UCLA to study open channel turbulent flow and heat transfer of low supercritical flow regimes (Fr /1), in which the surface waves are amplified and heat transfer is enhanced due

  3. Numerical Study of Convective Heat Transfer in Flat Tube Heat Exchangers Operating in Self-Sustained Oscillatory Flow Regimes 

    E-Print Network [OSTI]

    Fullerton, Tracy

    2012-02-14

    Laminar, two-dimensional, constant-property numerical simulations of flat tube heat exchanger devices operating in flow regimes in which self-sustained oscillations occur were performed. The unsteady flow regimes were ...

  4. Geothermal Well and Heat Flow Data for the United States (Southern Methodist University (SMU) Geothermal Laboratory)

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

    Blackwell, D.D. and others

    Southern Methodist University makes two databases and several detailed maps available. The Regional Heat Flow Database for the United States contains information on primarily regional or background wells that determine the heat flow for the United States; temperature gradients and conductivity are used to generate heat flow measurements. Information on geology of the location, porosity, thermal conductivity, water table depth, etc. are also included when known. There are usually three data files for each state or region. The first files were generated in 1989 for the data base creating the Decade of North America Geology (DNAG) Geothermal Map. The second set is from 1996 when the data base was officially updated for the Department of Energy. The third set is from 1999 when the Western U.S. High Temperature Geothermal data base was completed. As new data is received, the files continue to be updated. The second major resource is the Western Geothermal Areas Database, a database of over 5000 wells in primarily high temperature geothermal areas from the Rockies to the Pacific Ocean. The majority of the data are from company documents, well logs, and publications with drilling dates ranging from 1960 to 2000. Many of the wells were not previously accessible to the public. Users will need to register, but will then have free, open access to the databases. The contents of each database can be viewed and downloaded as Excel spreadsheets. See also the heat flow maps at http://www.smu.edu/geothermal/heatflow/heatflow.htm

  5. Spring temperatures in the Sagehen Basin, Sierra Nevada, CA: implications for heat flow and groundwater circulation

    E-Print Network [OSTI]

    Manga, Michael

    to an underestimate of heat flow in the Sierras based purely on borehole measurements. Using temperature and discharge­40 mW m)2 of geothermal heat from the basin. This is comparable with other heat flow measurements of geothermal heat within the basin. Additionally, we use esti- mates of the mean residence time of water

  6. Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Flow and heat transfer of a third grade fluid past an exponentially stretching sheet with partial-Newtonian boundary layer flow and heat transfer over an exponentially stretch- ing sheet with partial slip boundary. The heat transfer analysis has been carried out for two heating processes, namely (i) with prescribed sur

  7. Conductive and convective heat transfer in fluid flows between differentially heated and rotating cylinders

    E-Print Network [OSTI]

    Lopez, Jose M; Avila, Marc

    2015-01-01

    The flow of fluid confined between a heated rotating cylinder and a cooled stationary cylinder is a canonical experiment for the study of heat transfer in engineering. The theoretical treatment of this system is greatly simplified if the cylinders are assumed to be of infinite length or periodic in the axial direction, in which cases heat transfer occurs only through conduction as in a solid. We here investigate numerically heat transfer and the onset of turbulence in such flows by using both periodic and no-slip boundary conditions in the axial direction. We obtain a simple linear criterion that determines whether the infinite-cylinder assumption can be employed. The curvature of the cylinders enters this linear relationship through the slope and additive constant. For a given length-to-gap aspect ratio there is a critical Rayleigh number beyond which the laminar flow in the finite system is convective and so the behaviour is entirely different from the periodic case. The criterion does not depend on the Pra...

  8. Convection Heat Transfer in Three-Dimensional Turbulent Separated/Reattached Flow

    SciTech Connect (OSTI)

    Bassem F. Armaly

    2007-10-31

    The measurements and the simulation of convective heat transfer in separated flow have been a challenge to researchers for many years. Measurements have been limited to two-dimensional flow and simulations failed to predict accurately turbulent heat transfer in the separated and reattached flow region (prediction are higher than measurements by more than 50%). A coordinated experimental and numerical effort has been initiated under this grant for examining the momentum and thermal transport in three-dimensional separated and reattached flow in an effort to provide new measurements that can be used for benchmarking and for improving the simulation capabilities of 3-D convection in separated/reattached flow regime. High-resolution and non-invasive measurements techniques are developed and employed in this study to quantify the magnitude and the behavior of the three velocity components and the resulting convective heat transfer. In addition, simulation capabilities are developed and employed for improving the simulation of 3-D convective separated/reattached flow. Such basic measurements and simulation capabilities are needed for improving the design and performance evaluation of complex (3-D) heat exchanging equipment. Three-dimensional (3-D) convective air flow adjacent to backward-facing step in rectangular channel is selected for the experimental component of this study. This geometry is simple but it exhibits all the complexities that appear in any other separated/reattached flow, thus making the results generated in this study applicable to any other separated and reattached flow. Boundary conditions, inflow, outflow, and wall thermal treatment in this geometry can be well measured and controlled. The geometry can be constructed with optical access for non-intrusive measurements of the flow and thermal fields. A three-component laser Doppler velocimeter (LDV) is employed to measure simultaneously the three-velocity components and their turbulent fluctuations. Infrared thermography is utilized to measure the wall temperature and that information is used to determine the local convective heat transfer coefficient. FLUENT – CFD code is used as the platform in the simulation effort and User Defined Functions are developed for incorporating advanced turbulence models into this simulation code. Predictions of 3-D turbulent convection in separated flow, using the developed simulation capabilities under this grant, compared well with measured results. Results from the above research can be found in the seventeen refereed journal articles, and thirteen refereed publications and presentations in conference proceedings that have been published by the PI during the this grant period. The research effort is still going on and several publications are being prepared for reporting recent results.

  9. Infrared thermography of a pulsating heat pipe: Flow regimes and multiple steady states

    E-Print Network [OSTI]

    Khandekar, Sameer

    Infrared thermography of a pulsating heat pipe: Flow regimes and multiple steady states V t Understanding of the operational characteristics of a closed loop Pulsating Heat Pipe (PHP) with non- intrusive. Introduction A pulsating heat pipe/oscillating heat pipe is essentially a pas- sive two-phase heat transfer

  10. High Efficiency Microturbine with Integral Heat Recovery - Fact...

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

    Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 High Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 Capstone Turbine Corporation, in...

  11. High precision high flow range control valve

    DOE Patents [OSTI]

    McCray, J.A.

    1999-07-13

    A fluid control valve is described having a valve housing having first and second valve housing openings for the ingress and egress of fluid through the control valve. Disposed within a void formed by the control valve is a sleeve having at least one sleeve opening to permit the flow of fluid therethrough. A flow restricter travels within the sleeve to progressively block off the sleeve opening and thereby control flow. A fluid passageway is formed between the first valve housing opening and the outer surface of the sleeve. A second fluid passageway is formed between the inside of the sleeve and the second valve housing opening. Neither fluid passageway contains more than one 90 [degree] turn. In the preferred embodiment only one of the two fluid passageways contains a 90[degree] turn. In another embodiment, the control valve housing is bifurcated by a control surface having control surface opening disposed therethrough. A flow restricter is in slidable contact with the control surface to restrict flow of fluid through the control surface openings. 12 figs.

  12. High precision high flow range control valve

    DOE Patents [OSTI]

    McCray, John A. (Idaho Falls, ID)

    1999-01-01

    A fluid control valve is described having a valve housing having first and second valve housing openings for the ingress and egress of fluid through the control valve. Disposed within a void formed by the control valve is a sleeve having at least one sleeve opening to permit the flow of fluid therethrough. A flow restricter travels within the sleeve to progressively block off the sleeve opening and thereby control flow. A fluid passageway is formed between the first valve housing opening and the outer surface of the sleeve. A second fluid passageway is formed between the inside of the sleeve and the second valve housing opening. Neither fluid passageway contains more than one 90.degree. turn. In the preferred embodiment only one of the two fluid passageways contains a 90.degree. turn. In another embodiment, the control valve housing is bifurcated by a control surface having control surface opening disposed therethrough. A flow restricter is in slidable contact with the control surface to restrict flow of fluid through the control surface openings.

  13. The International Heat Flow Commission | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJ AutomationTexas/Wind Resources <forGermanInternational Heat Flow

  14. 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)

    2013-06-15

    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.

  15. Flow regimes and heat transfer in vertical narrow annuli

    SciTech Connect (OSTI)

    Ulke, A.; Goldberg, I.

    1993-11-01

    In shell side boiling heat exchangers narrow crevices that are formed between the tubes and the tube support structure provide areas for local thermal-hydraulic conditions which differ significantly from bulk fluid conditions. Understanding of the processes of boiling and dryout in flow restricted crevices can help in designing of tube support geometries to minimize the likelihood of tube support plate and tube corrosion observed in commercial power plant steam generators. This paper describes a one dimensional thermal-hydraulic model of a vertical crevice between a tube and a support plate with cylindrical holes. The annulus formed by the support plate hole and an eccentrically located tube has been represented by vertical strips. The formation, growth and collapse of a steam bubble in each strip has been determined. Based on the bubble history, and flow regimes characterized by ``isolated`` bubbles, ``coalesced`` bubbles and liquid deficient regions have been defined.

  16. Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow

    E-Print Network [OSTI]

    Marchese, Francis

    Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow Flow

  17. Temperature distribution in a flowing fluid heated in a microwave resonant cavity

    SciTech Connect (OSTI)

    Thomas, J.R. Jr. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States); Nelson, E.M.; Kares, R.J.; Stringfield, R.M. [Los Alamos National Lab., NM (United States)

    1996-04-01

    This paper presents results of an analytical study of microwave heating of a fluid flowing through a tube situated along the axis of a cylindrical microwave applicator. The interaction of the microwave field pattern and the fluid velocity profiles is illustrated for both laminar and turbulent flow. Resulting temperature profiles are compared with those generated by conventional heating through a surface heat flux. It is found that microwave heating offers several advantages over conventional heating.

  18. Unsteady laminar flow and convective heat transfer in a sharp 180 bend

    E-Print Network [OSTI]

    Chung, Yongmann M.

    Unsteady laminar flow and convective heat transfer in a sharp 180° bend Yongmann M. Chung a , Paul Unsteady laminar flow and heat transfer in a sharp 180° bend is studied numerically to investigate to be strong. Ó 2002 Elsevier Science Inc. All rights reserved. Keywords: Laminar; Unsteady; Heat transfer

  19. PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES

    E-Print Network [OSTI]

    Sen, Mihir

    PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES A Thesis Submitted April 1995 #12;PERFORMANCE OF A SINGLE-ROW HEAT EXCHANGER AT LOW IN-TUBE FLOW RATES by Xiangwei Zhao Abstract The steady and time-dependentbehavior of a single-row heat exchanger with water and air in the in

  20. 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 the dynamical effects from the heat transfer process. The fluid flow in an enclosed disk system with axial with heat transfer along the stator, which corresponds to the experiment of Djaoui et al. [2]. Our results

  1. Flow Boiling Heat Transfer Coefficient In Minichannels Correlation and Trends Satish G. Kandlikar

    E-Print Network [OSTI]

    Kandlikar, Satish

    Flow Boiling Heat Transfer Coefficient In Minichannels ­ Correlation and Trends Satish G. Kandlikar York 14623, USA The flow boiling heat transfer in small diameter passages is being applied in many boiling heat transfer coefficient with the correlations developed for conventional channels. It is found

  2. Friction and Heat Transfer Characteristics of Silica and CNT Nanofluids in a Tube Flow

    E-Print Network [OSTI]

    Kostic, Milivoje M.

    Friction and Heat Transfer Characteristics of Silica and CNT Nanofluids in a Tube Flow MILIVOJE M@niu.edu * www.kostic.niu.edu Abstract: - An apparatus for exploring friction and heat transfer characteristics flow. Initial turbulent friction and heat transfer measurements for silica and carbon nanotube (CNT

  3. 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

  4. Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law

    E-Print Network [OSTI]

    Boyer, Edmond

    Global weak solutions to magnetic fluid flows with nonlinear Maxwell-Cattaneo heat transfer law F transfer in a magnetic fluid flow under the action of an applied magnetic field. Instead of the usual heat-Cattaneo law, heat transfer, magnetic field, magnetization AMS subject classifications: 76N10, 35Q35. 1

  5. Continued development of a semianalytical solution for two-phase fluid and heat flow in a porous medium

    SciTech Connect (OSTI)

    Doughty, C.; Pruess, K. [Lawrence Berkeley Lab., CA (United States)

    1991-06-01

    Over the past few years the authors have developed a semianalytical solution for transient two-phase water, air, and heat flow in a porous medium surrounding a constant-strength linear heat source, using a similarity variable {eta} = r/{radical}t. Although the similarity transformation approach requires a simplified geometry, all the complex physical mechanisms involved in coupled two-phase fluid and heat flow can be taken into account in a rigorous way, so that the solution may be applied to a variety of problems of current interest. The work was motivated by adverse to predict the thermohydrological response to the proposed geologic repository for heat-generating high-level nuclear wastes at Yucca Mountain, Nevada, in a partially saturated, highly fractured volcanic formation. The paper describes thermal and hydrologic conditions near the heat source; new features of the model; vapor pressure lowering; and the effective-continuum representation of a fractured/porous medium.

  6. THERMAL DESIGN METHODOLOGY FOR LOW FLOW RATE SINGLE-PHASE AND TWO-PHASE MICRO-CHANNEL HEAT SINKS

    E-Print Network [OSTI]

    Qu, Weilin

    THERMAL DESIGN METHODOLOGY FOR LOW FLOW RATE SINGLE-PHASE AND TWO-PHASE MICRO-CHANNEL HEAT SINKS-phase micro- channel heat sinks under a fixed liquid coolant flow rate. The parameters relevant to heat sink-channel dimensions corresponding to the prescribed dissipative heat flux and liquid coolant flow rate. Heat sink

  7. High-bandwidth continuous-flow arc furnace

    DOE Patents [OSTI]

    Hardt, D.E.; Lee, S.G.

    1996-08-06

    A high-bandwidth continuous-flow arc furnace for stream welding applications includes a metal mass contained in a crucible having an orifice. A power source charges an electrode for generating an arc between the electrode and the mass. The arc heats the metal mass to a molten state. A pressurized gas source propels the molten metal mass through the crucible orifice in a continuous stream. As the metal is ejected, a metal feeder replenishes the molten metal bath. A control system regulates the electrode current, shielding gas pressure, and metal source to provide a continuous flow of molten metal at the crucible orifice. Independent control over the electrode current and shield gas pressure decouples the metal flow temperature and the molten metal flow rate, improving control over resultant weld characteristics. 4 figs.

  8. High-bandwidth continuous-flow arc furnace

    DOE Patents [OSTI]

    Hardt, David E. (Concord, MA); Lee, Steven G. (Ann Arbor, MI)

    1996-01-01

    A high-bandwidth continuous-flow arc furnace for stream welding applications includes a metal mass contained in a crucible having an orifice. A power source charges an electrode for generating an arc between the electrode and the mass. The arc heats the metal mass to a molten state. A pressurized gas source propels the molten metal mass through the crucible orifice in a continuous stream. As the metal is ejected, a metal feeder replenishes the molten metal bath. A control system regulates the electrode current, shielding gas pressure, and metal source to provide a continuous flow of molten metal at the crucible orifice. Independent control over the electrode current and shield gas pressure decouples the metal flow temperature and the molten metal flow rate, improving control over resultant weld characteristics.

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

    E-Print Network [OSTI]

    Shatto, Donald Patrick

    1997-01-01

    An experimental investigation has been conducted to determine the critical heat flux for subcooled refrigerant-11 and refrigerant-113 flowing upward in a vertical cylindrical tube. Critical heat flux (CHF) values are determined for a range of tube...

  10. A Variable Refrigerant Flow Heat Pump Computer Model in EnergyPlus

    SciTech Connect (OSTI)

    Raustad, Richard A. [Florida Solar Energy Center

    2013-01-01

    This paper provides an overview of the variable refrigerant flow heat pump computer model included with the Department of Energy's EnergyPlusTM whole-building energy simulation software. The mathematical model for a variable refrigerant flow heat pump operating in cooling or heating mode, and a detailed model for the variable refrigerant flow direct-expansion (DX) cooling coil are described in detail.

  11. Numerical study of high heat ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b

    E-Print Network [OSTI]

    Maruyama, Shigeo

    Numerical study of high heat ¯ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b , Shigeo simulation model of boiling heat transfer is proposed based on a numerical macrolayer model [S. Maruyama, M. Shoji, S. Shimizu, A numerical simulation of transition boiling heat transfer, in: Proceedings

  12. Two-phase flow and pressure drop in flow passages of compact heat exchangers

    SciTech Connect (OSTI)

    Wambsganss, M.W.; Jendrzejczyk, J.A.; France, D.M.

    1992-01-01

    Two-phase flow experiments were performed with air/water mixtures in a small rectangular channel measuring 9.52 {times} 1.59 mm (aspects ratio equal to 6), for applications to compact heat exchangers. Pressure drop and flow pattern definition data were obtained over a large range of mass qualities (0.0002 to 1), and in the case of flow pattern data, a large range of mass fluxes (50 to 2,000 kg/m{sup 2}s). A flow pattern map, based on visual observations and photographs of the flow patterns, is presented and compared with a map developed for a rectangular channel of the same aspect ratio but with dimensions twice those of the test channel, and with a map developed for a circular tube with the same hydraulic diameter of 3 mm. Pressure drop data are presented as a function of both mass quality and Martinelli parameter and are compared with state-of-the-art correlations and a modified Chisholm correlation. 13 refs.

  13. Two-phase flow and pressure drop in flow passages of compact heat exchangers

    SciTech Connect (OSTI)

    Wambsganss, M.W.; Jendrzejczyk, J.A.; France, D.M.

    1992-02-01

    Two-phase flow experiments were performed with air/water mixtures in a small rectangular channel measuring 9.52 {times} 1.59 mm (aspects ratio equal to 6), for applications to compact heat exchangers. Pressure drop and flow pattern definition data were obtained over a large range of mass qualities (0.0002 to 1), and in the case of flow pattern data, a large range of mass fluxes (50 to 2,000 kg/m{sup 2}s). A flow pattern map, based on visual observations and photographs of the flow patterns, is presented and compared with a map developed for a rectangular channel of the same aspect ratio but with dimensions twice those of the test channel, and with a map developed for a circular tube with the same hydraulic diameter of 3 mm. Pressure drop data are presented as a function of both mass quality and Martinelli parameter and are compared with state-of-the-art correlations and a modified Chisholm correlation. 13 refs.

  14. High energy density redox flow device

    DOE Patents [OSTI]

    Chiang, Yet-Ming; Carter, W. Craig; Ho, Bryan Y; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13

    Redox flow devices are described in which at least one of the positive electrode or negative electrode-active materials is a semi-solid or is a condensed ion-storing electroactive material, and in which at least one of the electrode-active materials is transported to and from an assembly at which the electrochemical reaction occurs, producing electrical energy. The electronic conductivity of the semi-solid is increased by the addition of conductive particles to suspensions and/or via the surface modification of the solid in semi-solids (e.g., by coating the solid with a more electron conductive coating material to increase the power of the device). High energy density and high power redox flow devices are disclosed. The redox flow devices described herein can also include one or more inventive design features. In addition, inventive chemistries for use in redox flow devices are also described.

  15. Phase change based cooling for high burst mode heat loads with temperature regulation above the phase change temperature

    DOE Patents [OSTI]

    The United States of America as represented by the United States Department of Energy (Washington, DC)

    2009-12-15

    An apparatus and method for transferring thermal energy from a heat load is disclosed. In particular, use of a phase change material and specific flow designs enables cooling with temperature regulation well above the fusion temperature of the phase change material for medium and high heat loads from devices operated intermittently (in burst mode). Exemplary heat loads include burst mode lasers and laser diodes, flight avionics, and high power space instruments. Thermal energy is transferred from the heat load to liquid phase change material from a phase change material reservoir. The liquid phase change material is split into two flows. Thermal energy is transferred from the first flow via a phase change material heat sink. The second flow bypasses the phase change material heat sink and joins with liquid phase change material exiting from the phase change material heat sink. The combined liquid phase change material is returned to the liquid phase change material reservoir. The ratio of bypass flow to flow into the phase change material heat sink can be varied to adjust the temperature of the liquid phase change material returned to the liquid phase change material reservoir. Varying the flowrate and temperature of the liquid phase change material presented to the heat load determines the magnitude of thermal energy transferred from the heat load.

  16. 2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 Molecular dynamics methods in

    E-Print Network [OSTI]

    Maruyama, Shigeo

    2.13 HEAT TRANSFER & FLUID FLOW IN MICROCHANNELS 2.13.7-1 2.13.7 Molecular dynamics methods in microscale heat transfer Shigeo Maruyama A. Introduction In normal heat transfer and fluid flow calculations of molecules. This situation is approached in microscale heat transfer and fluid flow. Molecular level

  17. 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.

    2013-04-01

    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.

  18. 1.12.2014bo Akademi Univ -Thermal and Flow Engineering Piispankatu 8, 20500 Turku 1/24 8. Heat pumps, heat pipes,

    E-Print Network [OSTI]

    Zevenhoven, Ron

    pumps, heat pipes, cold thermal energy storage Ron Zevenhoven Åbo Akademi University Thermal and Flow and Flow Engineering Piispankatu 8, 20500 Turku 2/24 8.1 Heat pumps #12;1.12.2014 Åbo Akademi Univ - Thermal and Flow Engineering Piispankatu 8, 20500 Turku 3/24 Heat pumps /1 Using a refrigeration cycle

  19. TEMPERATURE CONTROLLABILITY IN CROSS-FLOW HEAT EXCHANGERS AND LONG DUCTS

    E-Print Network [OSTI]

    Sen, Mihir

    TEMPERATURE CONTROLLABILITY IN CROSS-FLOW HEAT EXCHANGERS AND LONG DUCTS A Dissertation Submitted-FLOW HEAT EXCHANGERS AND LONG DUCTS Abstract by Sorour Abdulhadi Alotaibi The performance of thermal control and long ducts, are investigated, and the following issues are addressed. (a) The first is controllability

  20. Temperature-Gated Thermal Rectifier for Active Heat Flow Control Kedar Hippalgaonkar,,

    E-Print Network [OSTI]

    Wu, Junqiao

    Temperature-Gated Thermal Rectifier for Active Heat Flow Control Jia Zhu,, Kedar Hippalgaonkar to develop advanced all-thermal solid-state devices that actively control heat flow without consuming other of solid-state active-thermal devices with a large rectification in the Rectifier state. This temperature

  1. IINDIX IYITM DIVIIIOM ANN AIIOit, MICH. NO. 28-July-66 Heat Flow EYperiment

    E-Print Network [OSTI]

    Rathbun, Julie A.

    to forward Arthur D. Little manpower loading (for heat flow experiment} to MSC". .2 Prepared 0£: f' ~ W. E BY ARTHUR D. LITTLE Classifications Principal Staff Engineer Principal Staff Associate Engineer Executive. ?oCOil Approved by9d.~~/ J7 Jack E. Dye PAOli #12;28-July-66 Heat Flow Experiment NO. A I.DIX IYITIMI

  2. High flux heat transfer in a target environment

    E-Print Network [OSTI]

    McDonald, Kirk

    Valid for: Consider turbulent heat transfer in a 1.5mm diameter pipe ­ Dittus Boelter correlationHigh flux heat transfer in a target environment T. Davenne High Power Targets Group Rutherford · Radiation Cooling · Forced Convection · Nucleate Boiling · Critical Heat Flux · Other ideas · Summary #12

  3. Institute for High Heat Flux Removal (IHHFR). Phases I, II, and III

    SciTech Connect (OSTI)

    Boyd, Ronald D.

    2014-08-31

    The IHHFR focused on interdisciplinary applications as it relates to high heat flux engineering issues and problems which arise due to engineering systems being miniaturized, optimized, or requiring increased high heat flux performance. The work in the IHHFR focused on water as a coolant and includes: (1) the development, design, and construction of the high heat flux flow loop and facility; (2) test section development, design, and fabrication; and, (3) single-side heat flux experiments to produce 2-D boiling curves and 3-D conjugate heat transfer measurements for single-side heated test sections. This work provides data for comparisons with previously developed and new single-side heated correlations and approaches that address the single-side heated effect on heat transfer. In addition, this work includes the addition of single-side heated circular TS and a monoblock test section with a helical wire insert. Finally, the present work includes: (1) data base expansion for the monoblock with a helical wire insert (only for the latter geometry), (2) prediction and verification using finite element, (3) monoblock model and methodology development analyses, and (4) an alternate model development for a hypervapotron and related conjugate heat transfer controlling parameters.

  4. Large deviations in stochastic heat-conduction processes provide a gradient-flow structure for heat conduction

    SciTech Connect (OSTI)

    Peletier, Mark A., E-mail: m.a.peletier@tue.nl [Department of Mathematics and Computer Science and Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Postbus 513, 5600 MB Eindhoven (Netherlands); Redig, Frank, E-mail: f.h.j.redig@tudelft.nl [Delft Institute of Applied Mathematics, Technische Universiteit Delft, Mekelweg 4, 2628 CD Delft (Netherlands); Vafayi, Kiamars, E-mail: k.vafayi@tue.nl [Department of Mathematics and Computer Science, Technische Universiteit Eindhoven, Postbus 513, 5600 MB Eindhoven (Netherlands)

    2014-09-01

    We consider three one-dimensional continuous-time Markov processes on a lattice, each of which models the conduction of heat: the family of Brownian Energy Processes with parameter m (BEP(m)), a Generalized Brownian Energy Process, and the Kipnis-Marchioro-Presutti (KMP) process. The hydrodynamic limit of each of these three processes is a parabolic equation, the linear heat equation in the case of the BEP(m) and the KMP, and a nonlinear heat equation for the Generalized Brownian Energy Process with parameter a (GBEP(a)). We prove the hydrodynamic limit rigorously for the BEP(m), and give a formal derivation for the GBEP(a). We then formally derive the pathwise large-deviation rate functional for the empirical measure of the three processes. These rate functionals imply gradient-flow structures for the limiting linear and nonlinear heat equations. We contrast these gradient-flow structures with those for processes describing the diffusion of mass, most importantly the class of Wasserstein gradient-flow systems. The linear and nonlinear heat-equation gradient-flow structures are each driven by entropy terms of the form -log ?; they involve dissipation or mobility terms of order ?² for the linear heat equation, and a nonlinear function of ? for the nonlinear heat equation.

  5. Flow-Induced Deformation of a Flexible Thin Structure as Manifestation of Heat Transfer Enhancement

    E-Print Network [OSTI]

    Soti, Atul Kumar; Sheridan, John

    2015-01-01

    Flow-induced deformation of thin structures coupled with convective heat transfer has potential applications in energy harvesting and is important for understanding functioning of several biological systems. We numerically demonstrate large-scale flow-induced deformation as an effective passive heat transfer enhancement technique. An in-house, strongly-coupled fluid-structure interaction (FSI) solver is employed in which flow and structure solvers are based on sharp-interface immersed boundary and finite element method, respectively. In the present work, we validate convective heat transfer module of the in-house FSI solver against several benchmark examples of conduction and convective heat transfer including moving structure boundaries. The thermal augmentation is investigated as well as quantified for the flow-induced deformation of an elastic thin plate attached to lee side of a rigid cylinder in a heated channel laminar flow. We show that the wake vortices past the plate sweep higher sources of vorticity...

  6. Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01

    SciTech Connect (OSTI)

    Trehu, Anne; Kannberg, Peter

    2011-06-30

    The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity, and seafloor temperature. Direct observations of temperature at depth and physical properties of the sediment obtained from drilling can be used to calibrate the seismic observations, decreasing the uncertainty of the seismically-derived estimates. Anomalies in apparent heat flow can result from a variety of sources, including sedimentation, erosion, topographic refraction and fluid flow. We constructed apparent heat flow maps for portions of the Krishna-Godavari (K-G) basin, the Mahanadi basin, and the Andaman basin and modeled anomalies using 1-D conductive thermal models. Apparent heat flow values in the Krishna-Godavari (K-G) basin and Mahanadi basin are generally 0.035 to 0.055 watts per square meter (W/m2). The borehole data show an increase in apparent heat flow as water depth increases from 900 to 1500 m. In the SW part of the seismic grid, 1D modeling of the effect of sedimentation on heat flow shows that ~50% of the observed increase in apparent heat flow with increasing water depth can be attributed to trapping of sediments behind a "toe-thrust" ridge that is forming along the seaward edge of a thick, rapidly accumulating deltaic sediment pile. The remainder of the anomaly can be explained either by a decrease in thermal conductivity of the sediments filling the slope basin or by lateral advection of heat through fluid flow along stratigraphic horizons within the basin and through flexural faults in the crest of the anticline. Such flow probably plays a role in bringing methane into the ridge formed by the toe-thrust. Because of the small anomaly due to this process and the uncertainty in thermal conductivity, we did not model this process explicitly. In the NE part of the K-G basin seismic grid, a number of local heat flow lows and highs are observed, which can be attributed to topographic refraction and to local fluid flow along faults, respectively. No regional anomaly can be resolved. Because of lack of continuity between the K-G basin sites within the seismic grid and those ~70 km to the NE in water depths of 1200 to 1500 m, we do not speculate on the reason for higher heat flow at these depths. The Mahanadi basin results, while limited in geographic extent, are similar to those for the KG basin. The Andaman basin exhibits much lower apparent heat flow values, ranging from 0.015 to 0.025 W/m2. Heat flow here also appears to increase with increasing water depth. The very low heat flow here is among the lowest heat flow observed anywhere and gives rise to a very thick hydrate stability zone in the sediments. Through 1D models of sedimentation (with extremely high sedimentation rates as a proxy for tectonic thickening), we concluded that the very low heat flow can probably be attributed to the combined effects of high sedimentation rate, low thermal conductivity, tectonic thickening of sediments and the cooling effect of a subducting plate in a subduction zone forearc. Like for the K-G basin, much of the local variability can be attributed to topography. The regional increase in heat flow with water depth remains unexplained because the seismic grid available to us did not extend far enough to define the local tectonic setting of the slope basin controlling this observational pattern. The results are compared to results from other margins, both active and passive. While an increase in apparent heat flow with increasing water depth is widely observed, it is likely a result of different processes in different places. The very low heat flow due to sedimentation and tectonics in the Andaman basin is at the low end of glob

  7. Heat Flow and Gas Hydrates on the Continental Margin of India: Building on Results from NGHP Expedition 01

    SciTech Connect (OSTI)

    Anne Trehu; Peter Kannberg

    2011-06-30

    The Indian National Gas Hydrate Program (NGHP) Expedition 01 presented the unique opportunity to constrain regional heat flow derived from seismic observations by using drilling data in three regions on the continental margin of India. The seismic bottom simulating reflection (BSR) is a well-documented feature in hydrate bearing sediments, and can serve as a proxy for apparent heat flow if data are available to estimate acoustic velocity and density in water and sediments, thermal conductivity, and seafloor temperature. Direct observations of temperature at depth and physical properties of the sediment obtained from drilling can be used to calibrate the seismic observations, decreasing the uncertainty of the seismically-derived estimates. Anomalies in apparent heat flow can result from a variety of sources, including sedimentation, erosion, topographic refraction and fluid flow. We constructed apparent heat flow maps for portions of the Krishna-Godavari (K-G) basin, the Mahanadi basin, and the Andaman basin and modeled anomalies using 1-D conductive thermal models. Apparent heat flow values in the Krishna-Godavari (K-G) basin and Mahanadi basin are generally 0.035 to 0.055 watts per square meter (W/m{sup 2}). The borehole data show an increase in apparent heat flow as water depth increases from 900 to 1500 m. In the SW part of the seismic grid, 1D modeling of the effect of sedimentation on heat flow shows that {approx}50% of the observed increase in apparent heat flow with increasing water depth can be attributed to trapping of sediments behind a 'toe-thrust' ridge that is forming along the seaward edge of a thick, rapidly accumulating deltaic sediment pile. The remainder of the anomaly can be explained either by a decrease in thermal conductivity of the sediments filling the slope basin or by lateral advection of heat through fluid flow along stratigraphic horizons within the basin and through flexural faults in the crest of the anticline. Such flow probably plays a role in bringing methane into the ridge formed by the toe-thrust. Because of the small anomaly due to this process and the uncertainty in thermal conductivity, we did not model this process explicitly. In the NE part of the K-G basin seismic grid, a number of local heat flow lows and highs are observed, which can be attributed to topographic refraction and to local fluid flow along faults, respectively. No regional anomaly can be resolved. Because of lack of continuity between the K-G basin sites within the seismic grid and those {approx}70 km to the NE in water depths of 1200 to 1500 m, we do not speculate on the reason for higher heat flow at these depths. The Mahanadi basin results, while limited in geographic extent, are similar to those for the K-G basin. The Andaman basin exhibits much lower apparent heat flow values, ranging from 0.015 to 0.025 W/m{sup 2}. Heat flow here also appears to increase with increasing water depth. The very low heat flow here is among the lowest heat flow observed anywhere and gives rise to a very thick hydrate stability zone in the sediments. Through 1D models of sedimentation (with extremely high sedimentation rates as a proxy for tectonic thickening), we concluded that the very low heat flow can probably be attributed to the combined effects of high sedimentation rate, low thermal conductivity, tectonic thickening of sediments and the cooling effect of a subducting plate in a subduction zone forearc. Like for the K-G basin, much of the local variability can be attributed to topography. The regional increase in heat flow with water depth remains unexplained because the seismic grid available to us did not extend far enough to define the local tectonic setting of the slope basin controlling this observational pattern. The results are compared to results from other margins, both active and passive. While an increase in apparent heat flow with increasing water depth is widely observed, it is likely a result of different processes in different places. The very low heat flow due to sedimentation and tectonics in the Andaman basi

  8. Energy Efficient Process Heating: Managing Air Flow Kevin Carpenter and Kelly Kissock

    E-Print Network [OSTI]

    Kissock, Kelly

    Energy Efficient Process Heating: Managing Air Flow Kevin Carpenter and Kelly Kissock Department important aspect to consider when attempting to improve the energy efficiency of most process heating. Infiltration air enters the system through openings in the system shell. For energy- efficient process heating

  9. 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

  10. Heat transfer and friction characteristics of air flow in microtubes Chien-Yuh Yang a,

    E-Print Network [OSTI]

    Kandlikar, Satish

    Heat transfer and friction characteristics of air flow in microtubes Chien-Yuh Yang a, , Chia September 2011 Keywords: Microtube Heat transfer Liquid Crystal Thermography a b s t r a c t Several researches dealing with the single-phase forced convection heat transfer inside microchannels have been

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

    E-Print Network [OSTI]

    Rohsenow, Warren M.

    1951-01-01

    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 ...

  12. Heat transfer to air-water two-phase flow in slug/churn region

    SciTech Connect (OSTI)

    Wadekar, V.V. [AEA Technology, Harwell (United Kingdom). Heat Transfer and Fluid Flow Service; Tuzla, K.; Chen, J.C. [Lehigh Univ., Bethlehem, PA (United States). Dept. of Chemical Engineering

    1996-12-31

    Measured heat transfer data for air-water two-phase flow in the slug/churn flow region are reported. The measurements were obtained from a 1.3 m tall, 15.7 mm diameter vertical tube test-section. It is observed that the data exhibit different heat transfer characteristics to those predicted by the standard correlations for the convective component of flow boiling heat transfer. Comparison with the predictions of a slug flow model for evaporation shows a significant overprediction of the data. The reason for the overprediction is attributed to the sensible heating requirement of the gas phase. The slug flow model is therefore suitably modified for non-evaporating two-phase flow. This specially adapted model is found to give reasonably good predictions of the measured data.

  13. Heat transport and weakening of atmospheric stability induced by mesoscale flows

    E-Print Network [OSTI]

    Pielke, Roger A.

    Heat transport and weakening of atmospheric stability induced by mesoscale flows G. A. Dalu boundary layer (CBL) is transported upward into the midtroposphere by mesoscale flows, and how the air, and diffusion, associated with the mesoscale flow, is more clearly shown when the forcing is periodic in time

  14. DEVELOPMENT OF A HIGH PERFORMANCE COLD CLIMATE HEAT PUMP

    SciTech Connect (OSTI)

    Horton, W. Travis; Groll, Eckhard A.; Braun, James E.

    2014-06-01

    The primary goals of the proposed project were to develop, test, and evaluate a high performance and cost-effective vapor compression air-source heat pump for use in cold climate regions. Vapor compression heat pumps are a proven technology, and have been used for many years to meet heating requirements for buildings in residential, commercial, and industrial applications. However, in climate regions that experience very low outdoor ambient temperatures both the heating capacity and coefficient of performance (COP) of traditional air-source vapor compression heat pumps drops dramatically with a decrease in the outdoor air temperature. The efficiency of heat pumping equipment has improved substantially over the past 20 years; however, the efficiencies of the highest rated equipment on the market are approaching practical limits that cannot be surpassed without modifications to the basic cycle and possibly the use of additional hardware. In this report, three technologies to improve the efficiency of vapor compression systems are described. These are a) vapor injected compression, b) oil flooded compression and c) hybrid flow control of the evaporator. Compressor prototypes for both, oil flooded and vapor injected compression were developed by Emerson Climate Technologies. For the oil flooded compressor, the oil injection port location was optimized and an internal oil separator was added using several design iterations. After initial testing at Emerson Climate Technologies, further testing was done at Purdue University, and compressor models were developed. These models were then integrated into a system model to determine the achievable improvement of seasonal energy efficiency (SEER) for Minneapolis (Minnesota) climate. For the oil flooded compression, a 34% improvement in seasonal energy efficiency was found while a 21% improvement in seasonal energy efficiency ratio was found for the vapor injected compression. It was found that one benefit of both tested compression technologies is a lower discharge temperature, which allows for continued operation at lower ambient temperatures. A bin analysis of the vapor injected prototype cold climate heat pump predicts a 6% improvement in HSPF for Minneapolis. This improvement is mainly a result of the increased capacity of the system for active vapor injection. For the oil flooded system, a slightly larger performance improvement is predicted, in this case mostly caused by an increase in heating COP. Based on an economic analysis of these results, the maximum additional cost of the system changes, for the Minneapolis location, are $430 for the vapor injected system and $391 for the oil flooded system. These estimates assume that a 3-year simple payback period is accepted by the customer. For the hybrid flow control of evaporators, a new type of balancing valve was developed together with Emerson Climate technologies to reduce the cost of the control scheme. In contrast to conventional stepper motor valves, this valve requires less cables and can be driven by a cheaper output circuit on the control board. The correct valve size was determined in a dedicated test stand in several design iterations. The performance benefits of the hybrid control of the evaporator coil were determined for clean coil conditions as well as with partial blockage of the air inlet grille and under frosting conditions. For clean coil conditions, the benefits in terms of COP and capacity are negligible. However, significant benefits were noted for severely air-maldistributed operating conditions. For the H2-test, the maximum COP improvement of 17% along with a capacity improvement of nearly 40% was observed. Overall, the hybrid control scheme leads to a significant amount of performance improvement, if the air inlet conditions to the evaporator are maldistributed.

  15. Advanced High Porosity Ceramic Honeycomb Wall Flow Filters |...

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

    Porosity Ceramic Honeycomb Wall Flow Filters Advanced High Porosity Ceramic Honeycomb Wall Flow Filters 2007 Diesel Engine-Efficiency & Emissions Research Conference (DEER 2007)....

  16. Fusion Engineering and Design 81 (2006) 549553 Numerical analysis of MHD flow and heat transfer in a

    E-Print Network [OSTI]

    Abdou, Mohamed

    2006-01-01

    Fusion Engineering and Design 81 (2006) 549­553 Numerical analysis of MHD flow and heat transfer January 2006 Abstract MHD flow and heat transfer have been analyzed for a front poloidal channel blanket; Magnetohydrodynamics; Heat transfer 1. Introduction Using flow channel inserts (FCIs) made

  17. Bypass valve and coolant flow controls for optimum temperatures in waste heat recovery systems

    DOE Patents [OSTI]

    Meisner, Gregory P

    2013-10-08

    Implementing an optimized waste heat recovery system includes calculating a temperature and a rate of change in temperature of a heat exchanger of a waste heat recovery system, and predicting a temperature and a rate of change in temperature of a material flowing through a channel of the waste heat recovery system. Upon determining the rate of change in the temperature of the material is predicted to be higher than the rate of change in the temperature of the heat exchanger, the optimized waste heat recovery system calculates a valve position and timing for the channel that is configurable for achieving a rate of material flow that is determined to produce and maintain a defined threshold temperature of the heat exchanger, and actuates the valve according to the calculated valve position and calculated timing.

  18. Journal ofEnhanced Heat Transfer, 18 (3): 177-190 (2011) THERMALLY-INDUCED OSCILLATORY FLOW AND

    E-Print Network [OSTI]

    Zhang, Yuwen

    2011-01-01

    AND HEAT TRANSFER IN AN OSCILLATING HEAT PIPE Wei Shao & Yuwen Zhang* Department ofMechanical and Aerospace - a building block ofan Oscillating Heat Pipe (OHP) - is modeled by analyzing evaporation and condensation flow and by empirical correlationsfor a turbulent liquid flow. KEY WORDS: oscillating heat pipe

  19. Scanning electron microscopy study of carbon nanotubes heated at high temperatures in air

    E-Print Network [OSTI]

    . INTRODUCTION Because of their remarkable physical and electronic properties, carbon nanotubes are promising nanotubes in air,3,4 in an oxygen stream,5 or under a flow of carbon dioxide gas.6 Thinning of nanotubesScanning electron microscopy study of carbon nanotubes heated at high temperatures in air Xuekun Lu

  20. Low GWP Working Fluid for High Temperature Heat Pumps

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Low GWP Working Fluid for High Temperature Heat Pumps: DR-2 Chemical Stability at High Temperatures Temp Heat Pumps: DR-2 Very Low GWP AND Non-Flammable HFC-245fa DR-2 Chemical Formula CF3CH2CHF2 HFO 171.3 Pcr [MPa] 3.65 2.9 Kontomaris-DuPont; European Heat Pump Summit, Nuremberg, October 15th, 2013

  1. Heat Flow in VC-2A and VC-2B, and Constraints on the Thermal...

    Open Energy Info (EERE)

    Heat Flow in VC-2A and VC-2B, and Constraints on the Thermal Regime of the Valles Caldera, New Mexico Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  2. The Effects of Frost Growth on Finned Tube Heat Exchangers under Laminar Flow 

    E-Print Network [OSTI]

    Kondepudi, Sekhar

    1988-01-01

    A study on the effects of frost growth on the performance of finned tube heat exchangers under laminar flow has been conducted. The study was both experimental and analytical. The experimental part of the investigation ...

  3. Visualization of flow boiling in an annular heat exchanger under reduced gravity conditions 

    E-Print Network [OSTI]

    Westheimer, David Thomas

    2000-01-01

    poorly with an Earth based flow regime map; (ii) predicting that the maximum two-phase heat transfer coefficient would occur near the location the boiling fluid reached a saturated state, which also corresponded with the location of maximum nucleate...

  4. A Model of Plasma Heating by Large-Scale Flow

    E-Print Network [OSTI]

    Pongkitiwanichakul, P; Boldyrev, S; Mason, J; Perez, J C

    2015-01-01

    In this work we study the process of energy dissipation triggered by a slow large scale motion of a magnetized conducting fluid. Our consideration is motivated by the problem of heating the solar corona, which is believed to be governed by fast reconnection events set off by the slow motion of magnetic field lines anchored in the photospheric plasma. To elucidate the physics governing the disruption of the imposed laminar motion and the energy transfer to small scales, we propose a simplified model where the large-scale motion of magnetic field lines is prescribed not at the footpoints but rather imposed volumetrically. As a result, the problem can be treated numerically with an efficient, highly-accurate spectral method, allowing us to use a resolution and statistical ensemble exceeding those of the previous work. We find that, even though the large-scale deformations are slow, they eventually lead to reconnection events that drive a turbulent state at smaller scales. The small-scale turbulence displays many...

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

    E-Print Network [OSTI]

    Fithen, Robert Miller

    1987-01-01

    FINITE ELEMENT ANALYSIS OF CONJUGATE HEAT TRANSFER IN AXISYMMETRIC PIPE FLOWS A Thesis by ROBERT MILLER FITHEN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MA STER... OF S CI EN CE August 1987 Major Subject: Mechanical Engineering FINITE ELEMENT ANALYSIS OF CONJUGATE HEAT TRANSFER IN AXISYMMETRIC PIPE FLOWS A Thesis by ROBERT MILLER FITHEN Approved ss to style and content by: N. K. Anand (Chairman of Committee...

  6. NEW MODEL AND MEASUREMENT PRINCIPLE OF FLOWING AND HEAT TRANSFER CHARACTERISTICS OF REGENERATOR

    SciTech Connect (OSTI)

    Chen, Y. Y.; Luo, E. C.; Dai, W.

    2008-03-16

    Regenerators play key role in oscillating-flow cryocoolers or thermoacoustic heat engine systems. However, their flowing and heat transfer mechanism is still not well understood. The complexities of the oscillating flow regenerator make traditional method of heat transfer research become difficult or helpless. In this paper, a model for porous media regenerator was given based on the linear thermoacoustic theory. Then the correlations for characteristic parameters were obtained by deducing universal expressions for thermoacoustic viscous function F{sub v} and thermal function F{sub T}. A simple acoustical method and experimental system to get F{sub v} and F{sub T} via measurements of isothermal regenerators were presented. Some measurements of packed stainless screen regenerators were performed, and preliminary experimental results for flow and convective coefficients were derived, which showing flowing friction factor is approximately within 132/Re to 173/Re.

  7. Phonons and defects in semiconductors and nanostructures: Phonon trapping, phonon scattering, and heat flow at heterojunctions

    SciTech Connect (OSTI)

    Estreicher, S. K., E-mail: Stefan.Estreicher@ttu.edu; Gibbons, T. M.; Kang, By.; Bebek, M. B. [Physics Department, Texas Tech University, Lubbock, Texas 79409-1051 (United States)

    2014-01-07

    Defects in semiconductors introduce vibrational modes that are distinct from bulk modes because they are spatially localized in the vicinity of the defect. Light impurities produce high-frequency modes often visible by Fourier-transform infrared absorption or Raman spectroscopy. Their vibrational lifetimes vary by orders of magnitude and sometimes exhibit unexpectedly large isotope effects. Heavy impurities introduce low-frequency modes sometimes visible as phonon replicas in photoluminescence bands. But other defects such as surfaces or interfaces exhibit spatially localized modes (SLMs) as well. All of them can trap phonons, which ultimately decay into lower-frequency bulk phonons. When heat flows through a material containing defects, phonon trapping at localized modes followed by their decay into bulk phonons is usually described in terms of phonon scattering: defects are assumed to be static scattering centers and the properties of the defect-related SLMs modes are ignored. These dynamic properties of defects are important. In this paper, we quantify the concepts of vibrational localization and phonon trapping, distinguish between normal and anomalous decay of localized excitations, discuss the meaning of phonon scattering in real space at the atomic level, and illustrate the importance of phonon trapping in the case of heat flow at Si/Ge and Si/C interfaces.

  8. Transient Thermal, Hydraulic, and Mechanical Analysis of a Counter Flow Offset Strip Fin Intermediate Heat Exchanger using an Effective Porous Media Approach

    E-Print Network [OSTI]

    Urquiza, Eugenio

    2009-01-01

    for Compact Plate-Type Heat Exchangers. ” American Institutethese conditions, plate-type heat exchangers with small flowHeatric plate-type compact heat exchanger showing multiple

  9. Technical Subtopic 2.1: Modeling Variable Refrigerant Flow Heat Pump and Heat Recovery Equipment in EnergyPlus

    SciTech Connect (OSTI)

    Raustad, Richard; Nigusse, Bereket; Domitrovic, Ron

    2013-09-30

    The University of Central Florida/Florida Solar Energy Center, in cooperation with the Electric Power Research Institute and several variable-refrigerant-flow heat pump (VRF HP) manufacturers, provided a detailed computer model for a VRF HP system in the United States Department of Energy's (U.S. DOE) EnergyPlus? building energy simulation tool. Detailed laboratory testing and field demonstrations were performed to measure equipment performance and compare this performance to both the manufacturer's data and that predicted by the use of this new model through computer simulation. The project goal was to investigate the complex interactions of VRF HP systems from an HVAC system perspective, and explore the operational characteristics of this HVAC system type within a laboratory and real world building environment. Detailed laboratory testing of this advanced HVAC system provided invaluable performance information which does not currently exist in the form required for proper analysis and modeling. This information will also be useful for developing and/or supporting test standards for VRF HP systems. Field testing VRF HP systems also provided performance and operational information pertaining to installation, system configuration, and operational controls. Information collected from both laboratory and field tests were then used to create and validate the VRF HP system computer model which, in turn, provides architects, engineers, and building owners the confidence necessary to accurately and reliably perform building energy simulations. This new VRF HP model is available in the current public release version of DOE?s EnergyPlus software and can be used to investigate building energy use in both new and existing building stock. The general laboratory testing did not use the AHRI Standard 1230 test procedure and instead used an approach designed to measure the field installed full-load operating performance. This projects test methodology used the air enthalpy method where relevant air-side parameters were controlled while collecting output performance data at discreet points of steady-state operation. The primary metrics include system power consumption and zonal heating and cooling capacity. Using this test method, the measured total cooling capacity was somewhat lower than reported by the manufacturer. The measured power was found to be equal to or greater than the manufacturers indicated power. Heating capacity measurements produced similar results. The air-side performance metric was total cooling and heating energy since the computer model uses those same metrics as input to the model. Although the sensible and latent components of total cooling were measured, they are not described in this report. The test methodology set the thermostat set point temperature very low for cooling and very high for heating to measure full-load performance and was originally thought to provide the maximum available capacity. Manufacturers stated that this test method would not accurately measure performance of VRF systems which is now believed to be a true statement. Near the end of the project, an alternate test method was developed to better represent VRF system performance as if field installed. This method of test is preliminarily called the Load Based Method of Test where the load is fixed and the indoor conditions and unit operation are allowed to fluctuate. This test method was only briefly attempted in a laboratory setting but does show promise for future lab testing. Since variable-speed air-conditioners and heat pumps include an on-board control algorithm to modulate capacity, these systems are difficult to test. Manufacturers do have the ability to override internal components to accommodate certification procedures, however, it is unknown if the resulting operation is replicated in the field, or if so, how often. Other studies have shown that variable-speed air-conditioners and heat pumps do out perform their single-speed counterparts though these field studies leave as many questions as they do provide answers. The measure

  10. ARC-HEATED GAS FLOW EXPERIMENTS FOR HYPERSONIC PROPULSION

    E-Print Network [OSTI]

    Texas at Arlington, University of

    the Supersonic Wind Tunnel. I have enjoyed working with Rod Duke, who has been an important asset to my research to be injected into the engine combustors. To investigate this approach, the UTA Arc-Heated #12;vi Wind Tunnel

  11. 378 Solutions Manual x Fluid Mechanics, Fifth Edition where heat flow, J/s

    E-Print Network [OSTI]

    Bahrami, Majid

    378 Solutions Manual x Fluid Mechanics, Fifth Edition where heat flow, J/s A surface area, m Q 2 'T Ans. L V VV U PU § ·' : 3 3 3 3 ¨ ¸ © ¹ 5.18 Under laminar conditions, the volume flow Q through temperature difference, K The dimensionless form of h, called the Stanton number, is a combination of h, fluid

  12. Simplified model and lattice Boltzmann algorithm for microscale electro-osmotic flows and heat transfer

    E-Print Network [OSTI]

    Zhao, Tianshou

    Simplified model and lattice Boltzmann algorithm for microscale electro-osmotic flows and heat The extremely small length scale of the electric double layer (EDL) of electro-osmotic flows (EOF and temperature as the velocity-slip and temperature-jump boundary conditions, form a simple model for the electro-osmotic

  13. High Average Power Laser Gain Medium With Low Optical Distortion Using A Transverse Flowing Liquid Host

    DOE Patents [OSTI]

    Comaskey, Brian J. (Walnut Creek, CA); Ault, Earl R. (Livermore, CA); Kuklo, Thomas C. (Oakdale, CA)

    2005-07-05

    A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.

  14. Comparative Analysis of Natural Convection Flows Simulated by both the Conservation and Incompressible Forms of the Navier-Stokes Equations in a Differentially-Heated Square Cavity

    SciTech Connect (OSTI)

    Richard C. Martineau; Ray A. Berry; Aurélia Esteve; Kurt D. Hamman; Dana A. Knoll; Ryosuke Park; William Taitano

    2009-01-01

    This report illustrates a comparative study to analyze the physical differences between numerical simulations obtained with both the conservation and incompressible forms of the Navier-Stokes equations for natural convection flows in simple geometries. The purpose of this study is to quantify how the incompressible flow assumption (which is based upon constant density advection, divergence-free flow, and the Boussinesq gravitational body force approximation) differs from the conservation form (which only assumes that the fluid is a continuum) when solving flows driven by gravity acting upon density variations resulting from local temperature gradients. Driving this study is the common use of the incompressible flow assumption in fluid flow simulations for nuclear power applications in natural convection flows subjected to a high heat flux (large temperature differences). A series of simulations were conducted on two-dimensional, differentially-heated rectangular geometries and modeled with both hydrodynamic formulations. From these simulations, the selected characterization parameters of maximum Nusselt number, average Nusselt number, and normalized pressure reduction were calculated. Comparisons of these parameters were made with available benchmark solutions for air with the ideal gas assumption at both low and high heat fluxes. Additionally, we generated body force, velocity, and divergence of velocity distributions to provide a basis for further analysis. The simulations and analysis were then extended to include helium at the Very High Temperature gas-cooled Reactor (VHTR) normal operating conditions. Our results show that the consequences of incorporating the incompressible flow assumption in high heat flux situations may lead to unrepresentative results. The results question the use of the incompressible flow assumption for simulating fluid flow in an operating nuclear reactor, where large temperature variations are present. The results show that the use of the incompressible flow assumption with the Boussinesq gravitational body force approximation should be restricted to flows where the density change of a fluid particle along a pathline is negligible.

  15. Convective Heat Transfer Augmentation by Flexible fins in Laminar Channel Pulsating flow

    E-Print Network [OSTI]

    Joshi, Rakshitha U; Bhardwaj, Rajneesh

    2015-01-01

    Fluid-structure interaction (FSI) of thin flexible fins coupled with convective heat transfer has applications in energy harvesting and in understanding functioning of several biological systems. We numerically investigate FSI of the thin flexible fins involving large-scale flow-induced deformation as a potential heat transfer enhancement technique. An in-house, strongly-coupled fluid-structure interaction (FSI) solver is employed in which flow and structure solvers are based on sharp-interface immersed boundary and finite element method, respectively. We consider twin flexible fins in a heated channel with laminar pulsating cross flow. The vortex ring past the fin sweep higher sources of vorticity generated on the channel walls out into the downstream - promoting the mixing of the fluid. The moving fin assists in convective mixing, augmenting convection in bulk and at the walls; and thereby reducing thermal boundary layer thickness and improving heat transfer at the channel walls. The thermal augmentation is...

  16. Mapping Geothermal Heat Flow and Existing Plants | Department...

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

    new clean, renewable geothermal plants in the near future. EGS works by injecting cold water deep into the Earth's crust. This water flows through fissures and cracks in the...

  17. A numerical study on the effects of 2d structured sinusoidal elements on fluid flow and heat transfer at microscale

    E-Print Network [OSTI]

    Kandlikar, Satish

    , the effect of structured roughness elements on incompress- ible laminar fluid flow is analyzedA numerical study on the effects of 2d structured sinusoidal elements on fluid flow and heat flow Structured roughness elements Laminar flow a b s t r a c t Better understanding of laminar flow

  18. The Hardy inequality and the heat flow in curved wedges

    E-Print Network [OSTI]

    David Krejcirik

    2015-07-13

    We show that the polynomial decay rate of the heat semigroup of the Dirichlet Laplacian in curved planar wedges equals the sum of the usual dimensional decay rate and a multiple of the reciprocal value of the opening angle. To prove the result, we develop the method of self-similar variables for the associated heat equation and study the asymptotic behaviour of the transformed non-autonomous parabolic problem for large times. We also establish an improved Hardy inequality for the Dirichlet Laplacian in non-trivially curved wedges and state a conjecture about an improved decay rate in this case.

  19. A Detailed Analysis of Guard-Heated Wall Shear Stress Sensors for Turbulent Flows Seyed Ali Ale Etrati Khosroshahi

    E-Print Network [OSTI]

    Victoria, University of

    A Detailed Analysis of Guard-Heated Wall Shear Stress Sensors for Turbulent Flows by Seyed Ali Ale A Detailed Analysis of Guard-Heated Wall Shear Stress Sensors for Turbulent Flows by Seyed Ali Ale Etrati-dimensional analysis of the performance of multi-element guard-heated hot-film wall shear stress microsensors

  20. Statistical mechanical theory for steady-state systems. III. Heat flow in a Lennard-Jones fluid

    E-Print Network [OSTI]

    Attard, Phil

    Statistical mechanical theory for steady-state systems. III. Heat flow in a Lennard-Jones fluid March 2005; accepted 4 May 2005; published online 28 June 2005 A statistical mechanical theory for heat distribution for heat flow down an imposed thermal gradient is tested with simulations of a Lennard-Jones fluid

  1. Effect of rolling motion on critical heat flux for subcooled flow boiling in vertical tube

    SciTech Connect (OSTI)

    Hwang, J. S.; Park, I. U.; Park, M. Y.; Park, G. C.

    2012-07-01

    This paper presents defining characteristics of the critical heat flux (CHF) for the boiling of R-134a in vertical tube operation under rolling motion in marine reactor. It is important to predict CHF of marine reactor having the rolling motion in order to increase the safety of the reactor. Marine Reactor Moving Simulator (MARMS) tests are conducted to measure the critical heat flux using R-134a flowing upward in a uniformly heated vertical tube under rolling motion. MARMS was rotated by motor and mechanical power transmission gear. The CHF tests were performed in a 9.5 mm I.D. test section with heated length of 1 m. Mass fluxes range from 285 to 1300 kg m{sup -2}s{sup -1}, inlet subcooling from 3 to 38 deg. C and outlet pressures from 13 to 24 bar. Amplitudes of rolling range from 15 to 40 degrees and periods from 6 to 12 sec. To convert the test conditions of CHF test using R-134a in water, Katto's fluid-to-fluid modeling was used in present investigation. A CHF correlation is presented which accounts for the effects of pressure, mass flux, inlet subcooling and rolling angle over all conditions tested. Unlike existing transient CHF experiments, CHF ratio of certain mass flux and pressure are different in rolling motion. For the mass fluxes below 500 kg m{sup -2}s{sup -1} at 13, 16 (region of relative low mass flux), CHF ratio was decreased but was increased above that mass flux (region of relative high mass flux). Moreover, CHF tend to enhance in entire mass flux at 24 bar. (authors)

  2. Heat flows and energetic behavior of a telecommunication radio base station

    E-Print Network [OSTI]

    Petraglia, Antonio; Vetromile, Carmela; D'Onofrio, Antonio; Lubritto, Carmine

    2015-01-01

    This paper shows a study on energetic consumption of BTSs (Base Transceiver Stations) for mobile communication, related to conditioning functions. An energetic "thermal model" of a telecommunication station is proposed and studied. The results have been validated with a BTS in central Italy, showing good agreement. Findings show a substantial high internal-external temperature difference in the containing shelter, particularly during daytime and warm months, due to sources of heat (equipment, external temperature and sun radiation) and to the difficulty in spread the warmth out. The necessity to keep the operating temperatures within a given range for the correct functioning of the electronic equipment requires the use of conditioning setups, and this significantly increases the energetic demand of the whole system. The analysis of thermal flows across the shelter can help to gather further data on its temperature behavior and to devise practical measures to lower the power demand, while keeping the operating...

  3. Emissivity corrected infrared method for imaging anomalous structural heat flows

    DOE Patents [OSTI]

    Del Grande, Nancy K. (San Leandro, CA); Durbin, Philip F. (Livermore, CA); Dolan, Kenneth W. (Livermore, CA); Perkins, Dwight E. (Livermore, CA)

    1995-01-01

    A method for detecting flaws in structures using dual band infrared radiation. Heat is applied to the structure being evaluated. The structure is scanned for two different wavelengths and data obtained in the form of images. Images are used to remove clutter to form a corrected image. The existence and nature of a flaw is determined by investigating a variety of features.

  4. A Cross-Flow Ceramic Heat Recuperator for Industrial Heat Recovery 

    E-Print Network [OSTI]

    Gonzalez, J. M.; Cleveland, J. J.; Kohnken, K. H.; Rebello, W. J.

    1980-01-01

    With increasing fuel costs, the efficient use of fuel is very important to the U.S. process heat industries. Increase in fuel usage efficiency can be obtained by transferring the waste exhaust heat to the cold combustion air. The metallic...

  5. Heat flow and seismicity patterns in the vicinity of the eastern Snake River Plain, Idaho

    SciTech Connect (OSTI)

    Blackwell, D.D. Kelley, S.A.; Steele, J.L. (Southern Methodist Univ., Dallas, TX (United States). Dept. of Geological Sciences)

    1993-04-01

    New heat flow data and thermal modeling are used to calculate crustal temperatures in and adjacent to the eastern Snake River Plain (SRP). The estimated crustal temperature are then used to investigate the relationship between crustal strength and the observed parabolic pattern of seismicity around the SRP. Heat flow below the SRP aquifer in deep wells on the Idaho National Engineering Laboratory (INEL) site near the northern margin of the SRP is 107 [plus minus] 15 mWm[sup [minus]2]. Heat flow values from deep wells on both the northern and southern margins of the eastern SRP average 100 [plus minus] 15 mWm[sup [minus]2]. 2-D finite-difference thermal models were developed to fit seismic and heat flow data in the vicinity of the SRP. The models have a shallow silicic magma chamber that is as wide as the SRP. The silicic chamber is underlain by mafic heat sources in the middle to lower crust and in the upper mantle. The heat flow data are best fit by models with deep heat sources that are wider than the SRP. These results are consistent with the presence of young basaltic centers that have been observed outside the SRP. The temperature from the authors thermal models were used to calculate strength envelopes for the crust in the SRP/Basin and Range region. The weakest part of the crust is along the edge of the Basin and Range, where it is heated by the SRP; thus the boundary to the two provinces may be a zone of weak coupling. Their modeling indicates that it is difficult to explain the earthquake pattern in the vicinity of the SRP as a thermomechanical effect related to the passage of the Yellowstone hot spot.

  6. Emissivity corrected infrared method for imaging anomalous structural heat flows

    DOE Patents [OSTI]

    Del Grande, N.K.; Durbin, P.F.; Dolan, K.W.; Perkins, D.E.

    1995-08-22

    A method for detecting flaws in structures using dual band infrared radiation is disclosed. Heat is applied to the structure being evaluated. The structure is scanned for two different wavelengths and data obtained in the form of images. Images are used to remove clutter to form a corrected image. The existence and nature of a flaw is determined by investigating a variety of features. 1 fig.

  7. Geothermal Heat Flow and Existing Geothermal Plants | Department of Energy

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE: Alternative Fuelsof Energy Services »Information ResourcesHeatGenericExploration

  8. Counter flow cooling drier with integrated heat recovery

    DOE Patents [OSTI]

    Shivvers, Steve D. (Prole, IA)

    2009-08-18

    A drier apparatus for removing water or other liquids from various materials includes a mixer, drying chamber, separator and regenerator and a method for use of the apparatus. The material to be dried is mixed with a heated media to form a mixture which then passes through the chamber. While passing through the chamber, a comparatively cool fluid is passed counter current through the mixture so that the mixture becomes cooler and drier and the fluid becomes hotter and more saturated with moisture. The mixture is then separated into drier material and media. The media is transferred to the regenerator and heated therein by the hot fluid from the chamber and supplemental heat is supplied to bring the media to a preselected temperature for mixing with the incoming material to be dried. In a closed loop embodiment of the apparatus, the fluid is also recycled from the regenerator to the chamber and a chiller is utilized to reduce the temperature of the fluid to a preselected temperature and dew point temperature.

  9. Use Remote Sensing Data (selected visible and infrared spectrums) to locate high temperature ground anomalies in Colorado. Confirm heat flow potential with on-site surveys to drill deep resource wells

    Broader source: Energy.gov [DOE]

    DOE Geothermal Technologies Peer Review 2010 - Presentation. Project Objectives: A cost effective three (3) Phased Program to locate and confirm up to Five (5) commercial geothermal resources in Colorado. The heat resources to be prioritized will be those able to support a minimum electrical generation capacity of 10 MW by location.

  10. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, Kwan H. (Naperville, IL); Ahluwalia, Rajesh K. (Burr Ridge, IL)

    1994-01-01

    A radiative heat transfer mechanism in a furnace having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits.

  11. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, K.H.; Ahluwalia, R.K.

    1994-10-18

    A radiative heat transfer mechanism in a furnace is described having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits. 7 figs.

  12. An experimental study of endwall heat transfer enhancement for flow past staggered non-conducting pin fin arrays 

    E-Print Network [OSTI]

    Achanta, Vamsee Satish

    2004-09-30

    In this work, we study the enhanced endwall heat transfer for flow past non conducting pin fin arrays. The aim is to resolve the controversy over the heat transfer that is taking place from the endwall and the pin ...

  13. Time variability of AGN and heating of cooling flows

    E-Print Network [OSTI]

    Carlo Nipoti; James Binney

    2005-05-03

    There is increasing evidence that AGN mechanical feedback is important in the energetics of cooling flows in galaxies and galaxy clusters. We investigate the implications of the variability of AGN mechanical luminosity L_m on observations of cooling flows and radio galaxies in general. It is natural to assume that l=ln(L_m/L_x) is a Gaussian process. Then L_m will be log-normally distributed at fixed cooling luminosity L_x, and the variance in a measure of L_m will increase with the time-resolution of the measure. We test the consistency of these predictions with existing data. These tests hinge on the power spectrum of l(t). Monitoring of Seyfert galaxies combined with estimates of the duty cycle of quasars imply flicker noise spectra, similar to those of microquasars. We combine a sample of sources in cooling flows that have cavities with the assumption that the average mechanical luminosity of the AGN equals L_x. Given that the mechanical luminosities are characterized by flicker noise, we find that their spectral amplitudes lie between the estimated amplitudes of quasars and the measured values for the radio luminosities of microquasars. The model together with the observation that powerful radio galaxies lie within a narrow range in optical luminosity, predicts the luminosity function of radio galaxies, in agreement with observations. Forthcoming radio surveys will test the prediction that the luminosity function turns over at about the smallest luminosities so far probed. [Abridged

  14. High speed flow cytometric separation of viable cells

    DOE Patents [OSTI]

    Sasaki, Dennis T. (Mountain View, CA); Van den Engh, Gerrit J. (Seattle, WA); Buckie, Anne-Marie (Margate, GB)

    1995-01-01

    Hematopoietic cell populations are separated to provide cell sets and subsets as viable cells with high purity and high yields, based on the number of original cells present in the mixture. High-speed flow cytometry is employed using light characteristics of the cells to separate the cells, where high flow speeds are used to reduce the sorting time.

  15. An analysis of periodic heat flow through a plane slab 

    E-Print Network [OSTI]

    Gibson, Daniel Morgan

    1958-01-01

    = heat ener;;y ter perature temperature at end o" time interval w8 nor~el distance from the surface in contact t. ~ith the fluid mhose te", . perature va~ies time prefix, a finite increment densit~J of the slab Sbs '* the fluid. v... INT. HiICH GLIC"' Zigure 2 The al. ;, ebra'c e-lressions for calculating7 the amount of ener'-y er terin;. = an7 interior slice through eaca of its l&oundaries during a finite time interval nQ and. the con- sequent change in energy content...

  16. DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 2

    SciTech Connect (OSTI)

    Not Available

    1992-06-01

    The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance personnel, and the technical staff with the necessary fundamentals training to ensure a basic understanding of the thermal sciences. The handbook includes information on thermodynamics and the properties of fluids; the three modes of heat transfer -- conduction, convection, and radiation; and fluid flow, and the energy relationships in fluid systems. This information will provide personnel with a foundation for understanding the basic operation of various types of DOE nuclear facility fluid systems.

  17. TOUGH Simulations of the Updegraff's Set of Fluid and Heat Flow Problems

    SciTech Connect (OSTI)

    Moridis, G.J.; Pruess (editor), K.

    1992-11-01

    The TOUGH code [Pruess, 1987] for two-phase flow of water, air, and heat in penneable media has been exercised on a suite of test problems originally selected and simulated by C. D. Updegraff [1989]. These include five 'verification' problems for which analytical or numerical solutions are available, and three 'validation' problems that model laboratory fluid and heat flow experiments. All problems could be run without any code modifications (*). Good and efficient numerical performance, as well as accurate results were obtained throughout. Additional code verification and validation problems from the literature are briefly summarized, and suggestions are given for proper applications of TOUGH and related codes.

  18. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, R.R.

    1984-07-16

    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.

  19. Electrically heated particulate filter with zoned exhaust flow control

    DOE Patents [OSTI]

    Gonze, Eugene V [Pinckney, MI

    2012-06-26

    A system includes a particulate matter (PM) filter that includes X zones. An electrical heater includes Y heater segments that are associated with respective ones of the X zones. The electrical heater is arranged upstream from and proximate with the PM filter. A valve assembly includes Z sections that are associated with respective ones of the X zones. A control module adjusts flow through each of the Z sections during regeneration of the PM filter via control of the valve assembly. X, Y and Z are integers.

  20. Investigation of Groundwater Flow in Foothill and Mountain regions using Heat Flow measurements

    E-Print Network [OSTI]

    Fogg, Graham E.; Trask, James C

    2009-01-01

    1965) Rates of Vertical Groundwater Movement Estimated fromCrystalline Rocks. Groundwater, Vol. 2, pp. 6-12. Dettinger,horizontal and vertical groundwater flow components. Water

  1. Numerical study of oscillatory flow and heat transfer in a loaded thermoacoustic stack

    SciTech Connect (OSTI)

    Worlikar, A.S.; Knio, O.M.

    1999-01-01

    A thermoacoustic refrigerator may be idealized as consisting of a straight resonance tube housing a stack of parallel plates and heat exchangers, and an acoustic source. Among the advantages of thermoacoustic refrigerators are the simplicity of their design and the fact that they naturally avoid the need for harmful refrigerants such as chlorofluorocarbons (CFCs). The operation of these devices is based on exploiting the well-known thermoacoustic effect to induce a temperature difference across the stack and to transport heat from one end of the plate to the other. Heat exchangers are then used to transfer energy from the thermoacoustic refrigerator to hot and cold reservoirs. A two-dimensional, low-Mach-number computational model is used to analyze the unsteady flow and temperature fields in the neighborhood of an idealized stack/heat exchanger configuration. The model relies on a vorticity-based formulation of the mass, momentum, and energy equations in the low-Mach-number, short-stack limit. The stack and heat exchangers are assumed to consist of flat plates of equal thickness. The heat exchanger plates are assumed isothermal and in perfect thermal contact with the stack plates. The simulations are used to study the effect of heat exchanger size and operating conditions on the heat transfer and stack performance. Computed results show that optimum stack performance is achieved when the length of the heat exchanger is nearly equal to the peak-to-peak particle displacement. Numerical estimates of the mean enthalpy flux within the channel are in good agreement with the predictions of linear theory. However, the results reveal that a portion of the heat exchangers is ineffective due to reverse heat transfer. Details of the energy flux density around the heat exchangers are visualized, and implications regarding heat exchanger design and model extension are discussed.

  2. High-Efficiency Quantum-Well Thermoelectrics for Waste Heat Power...

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

    High-Efficiency Quantum-Well Thermoelectrics for Waste Heat Power Generation High-Efficiency Quantum-Well Thermoelectrics for Waste Heat Power Generation 2005 Diesel Engine...

  3. High Efficiency Cold Climate Heat Pump

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh Efficiency Cold Climate

  4. CLARKSON UNIVERSITY AERODYNAMIC FLOW CONTROL OF A HIGH LIFT SYSTEM

    E-Print Network [OSTI]

    Bollt, Erik

    CLARKSON UNIVERSITY AERODYNAMIC FLOW CONTROL OF A HIGH LIFT SYSTEM WITH DUAL SYNTHETIC JET ARRAYS Flow Control of a High Lift System with Dual Synthetic Jet Arrays' presented by Robert Bruce Alstrom the performance of the latest generation aircraft by reducing their fuel consumption and improving their high

  5. November 28, 2006 Seismologists get handle on heat flow deep in earth

    E-Print Network [OSTI]

    Garnero, Ed

    November 28, 2006 Seismologists get handle on heat flow deep in earth Earth's interior placid inner Earth as a dynamic environment filled with exotic materials and substances roiling under that has an impact on what happens on our planet's surface. The latest evidence of this dynamic inner Earth

  6. Heat flow into spheres for a class of energies Norbert Hungerbuhler

    E-Print Network [OSTI]

    Hungerbühler, Norbert

    Heat flow into spheres for a class of energies Norbert Hungerb¨uhler Department of Mathematics Riemannian manifolds without boundaries. Then, for a map u : M N, we consider a class of energies which includes the popular Dirichlet energy and the more general p-energy. Geometric or physical questions

  7. Investigation of transient, two-dimensional coupled heat and moisture flow in soils

    SciTech Connect (OSTI)

    Shen, L.S.W.

    1986-01-01

    A two-dimensional finite difference numerical model has been developed to study coupled heat and moisture flow in the soil surrounding an earth-sheltered construction. The model is based on a mechanistic approach formulated by Milly and developed from the work of Philip and deVries. Using soil temperatures and matric potentials as the dependent variables, the model is capable of simulating unsaturated/saturated flow conditions in heterogeneous soil domains. The model is a fully implicit, integrated finite difference approach based on the Patankar Spalding method. The numerical modeling of the governing heat and moisture equations was validated against a number of analytical and quasi-analytical solutions. An axisymmetric, two-dimensional experiment was then defined to which the numerical model could be compared. The experimental apparatus was composed of a cylinder filled with a dredged Mississippi River sand. A series of one and two dimensional heat and moisture flow experiments were run, using boundary conditions consistent with those that occur in the soil surrounding a building. Soil properties used in the model were either calculated from theoretical models or measured experimentally. Agreement between the model and experiments were good, with an error of 10-15% obtained for the two-dimensional coupled heat and moisture flow experiment.

  8. High-pressure three-phase fluidization: Hydrodynamics and heat transfer

    SciTech Connect (OSTI)

    Luo, X.; Jiang, P.; Fan, L.S.

    1997-10-01

    High-pressure operations are common in industrial applications of gas-liquid-solid fluidized-bed reactors for resid hydrotreating, Fischer-Tropsch synthesis, coal methanation, methanol synthesis, polymerization, and other reactions. The phase holdups and the heat-transfer behavior were studied experimentally in three-phase fluidized beds over a pressure range of 0.1--15.6 MPa. Bubble characteristics in the bed are examined by direct flow visualization. Pressure effects on the bubble coalescence and breakup are analyzed mechanistically. The study indicates that the pressure affects the hydrodynamics and heat-transfer properties of a three-phase fluidized bed significantly. The average bubble size decreases and the bubble-size distribution becomes narrower with an increase in pressure. The bubble-size reduction leads to an increase in the transition gas velocity from the dispersed bubble regime to the coalesced bubble regime, an increase in the gas holdup, and a decrease in the liquid and solids holdups. The pressure effect is insignificant above 6 MPa. The heat-transfer coefficient between an immersed surface and the bed increases to a maximum at pressure 6--8 MPa and then decreases with an increase in pressure at a given gas and liquid flow rate. This variation is attributed to the pressure effects on phase holdups and physical properties of the gas and liquid phases. A mechanistic analysis revealed that the major heat-transfer resistance in high-pressure three-phase fluidized beds resides in a liquid film surrounding the heat-0transfer surface. An empirical correlation is proposed to predict the heat-transfer coefficient under high-pressure conditions.

  9. Dependence of heat transport on the strength and shear rate of prescribed circulating flows

    E-Print Network [OSTI]

    Emily S. C. Ching; K. M. Pang

    2001-11-28

    We study numerically the dependence of heat transport on the maximum velocity and shear rate of physical circulating flows, which are prescribed to have the key characteristics of the large-scale mean flow observed in turbulent convection. When the side-boundary thermal layer is thinner than the viscous boundary layer, the Nusselt number (Nu), which measures the heat transport, scales with the normalized shear rate to an exponent 1/3. On the other hand, when the side-boundary thermal layer is thicker, the dependence of Nu on the Peclet number, which measures the maximum velocity, or the normalized shear rate when the viscous boundary layer thickness is fixed, is generally not a power law. Scaling behavior is obtained only in an asymptotic regime. The relevance of our results to the problem of heat transport in turbulent convection is also discussed.

  10. Flow boiling and two-phase flow instabilities in silicon microchannel heat sinks for microsystems cooling 

    E-Print Network [OSTI]

    Bogojevi?, Dario

    2010-01-01

    Flow boiling in microchannels, while very promising as a cooling technology in electronics thermal management, is still a subject being explored that requires further investigation. Before applying this technology for ...

  11. A WIND TUNNEL INVESTIGATION OF THE INFLUENCE OF SOLAR-INDUCED WALL-HEATING ON THE FLOW REGIME

    E-Print Network [OSTI]

    Savory, Eric

    -section canyon model in a wind tunnel. For reference purposes, the neutral case (no wall heating), has also been viscosity of air (m2 s-1 ) 1. Introduction The wind flow field within urban areas has been studiedA WIND TUNNEL INVESTIGATION OF THE INFLUENCE OF SOLAR-INDUCED WALL-HEATING ON THE FLOW REGIME

  12. Turbulent heat transfer in a channel flow at transitional Reynolds numbers

    E-Print Network [OSTI]

    Tsukahara, Takahiro

    2014-01-01

    Direct numerical simulation of a turbulent channel flow with heat transfer was performed at very low Reynolds numbers. Two different thermal boundary conditions were studied, and temperature was considered as a passive scalar. The computations were carried out with huge computational boxes (up to 327.7 x 2 x 128 in the streamwise, wall-normal, and spanwise directions, respectively). The emphases of this paper are to investigate the large-scale structure (puff) in the intermittent-turbulent flow including the scalar fields and to provide the values of the transitional and critical Reynolds numbers, below which the turbulent flow becomes intermittent and laminar, respectively. The statistics, such as the skin friction and the Stanton number, were also examined: they suggest that the puff should be effective in sustaining turbulence and in heat transfer enhancement.

  13. Heat transfer and flow of an impinged plate with an elliptic jet

    SciTech Connect (OSTI)

    Matsuda, Shoichi; Yaga, Minoru; Oyakawa, Kenyu

    1999-07-01

    The time and spatial temperature profiles on a jet impingement plate were measured using an infrared radiometer with a two-dimensional array of Indium-Antimony (In Sb) sensors for various nozzle exit-to-plate spaces for when the jet being issued from an elliptic nozzle impinges on the target plate. The isotherms of infrared images as well as heat transfer coefficients were obtained by measurement data. The heat transfer coefficients were also measured by using thermocouples. In order to compare the isotherms and heat transfer contours with flow patterns, the flows on the plate were visualized by the oil-film method, and the velocity and the turbulence intensity were measured by a hot wire anemometer. The phenomena of axes switching which are caused by the differences in self-induced velocity in non-circular vortices and have been the typical behaviors of free jets were observed on the impingement plate. The distribution of the isotherm and iso-heat transfer coefficients for the center portion were shorted in the major direction with an increase of the space between nozzle exit and impingement plate and elongated in the minor direction. The isotherms from the infrared image corresponded closely to the distribution of iso-heat transfer coefficients by using thermocouples. The shapes of flow patterns also corresponded to both the shape of the isotherms and the iso-heat transfer contours. In the twice length of nozzle diameter downstream from nozzle exit, the oil film pattern was elongated in the major axis direction for the center portion, which corresponded to both the lower temperature and higher heat transfer coefficient.

  14. High-power ELF radiation generated by modulated HF heating of the ionosphere can cause Earthquakes, Cyclones and localized heating

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    transmitter radiates a strong beam of high- frequency (HF) waves modulated at ELF. This HF heating modulates-frequency (HF) radiation in the megahertz range [7]. This heating modulates the electron's temperature in the D

  15. Woven heat exchanger

    DOE Patents [OSTI]

    Piscitella, Roger R. (Idaho Falls, ID)

    1987-01-01

    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.

  16. Sandia Energy - Phononic Crystals: Engineering the Flow of Heat

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust, High-Throughput AnalysisSinkhole Officials Turn to Sandia NationalAdvancedeffects

  17. LIQUID-FLUIDIZED-BED HEAT' EXCHANGER FLOW DISTRIBUTION MODELS

    Office of Scientific and Technical Information (OSTI)

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield MunicipalTechnical Report:Speeding accessby aLED Street LightingFrom theHighI _s - s i s i^ -RS 1

  18. Optimal operation of a concurrent-flow corn dryer with a drying heat pump using superheated steam

    SciTech Connect (OSTI)

    Moraitis, C.S. [Systelligence Consultants and Research Associates, Volos (Greece); Akritidis, C.B. [Dept. of Hydraulics and Agricultural Engineering, Thessaloniki (Greece)

    1998-07-01

    A numerical model of a concurrent-flow dryer of corn using superheated steam as drying medium is solved applying a shooting technique, so as to satisfy boundary conditions imposed by the optimal design of a drying heat pump. The drying heat pump is based on the theory of minimum energy cycles. The solution of the model proves the applicability of the heat pump to a concurrent-flow dryer, achieving a Specific Energy Consumption as low as 1080 kJ/kg.

  19. THE INTEGRATION OF PROCESS HEAT APPLICATIONS TO HIGH TEMPERATURE GAS REACTORS

    SciTech Connect (OSTI)

    Michael G. McKellar

    2011-11-01

    A high temperature gas reactor, HTGR, can produce industrial process steam, high-temperature heat-transfer gases, and/or electricity. In conventional industrial processes, these products are generated by the combustion of fossil fuels such as coal and natural gas, resulting in significant emissions of greenhouse gases such as carbon dioxide. Heat or electricity produced in an HTGR could be used to supply process heat or electricity to conventional processes without generating any greenhouse gases. Process heat from a reactor needs to be transported by a gas to the industrial process. Two such gases were considered in this study: helium and steam. For this analysis, it was assumed that steam was delivered at 17 MPa and 540 C and helium was delivered at 7 MPa and at a variety of temperatures. The temperature of the gas returning from the industrial process and going to the HTGR must be within certain temperature ranges to maintain the correct reactor inlet temperature for a particular reactor outlet temperature. The returning gas may be below the reactor inlet temperature, ROT, but not above. The optimal return temperature produces the maximum process heat gas flow rate. For steam, the delivered pressure sets an optimal reactor outlet temperature based on the condensation temperature of the steam. ROTs greater than 769.7 C produce no additional advantage for the production of steam.

  20. Bayonet heat exchangers in heat-assisted Stirling heat pump

    SciTech Connect (OSTI)

    Yagyu, S.; Fukuyama, Y.; Morikawa, T.; Isshiki, N.; Satoh, I.; Corey, J.; Fellows, C.

    1998-07-01

    The Multi-Temperature Heat Supply System is a research project creating a city energy system with lower environmental load. This system consists of a gas-fueled internal combustion engine and a heat-assisted Stirling heat pump utilizing shaft power and thermal power in a combination of several cylinders. The heat pump is mainly driven by engine shaft power and is partially assisted by thermal power from engine exhaust heat source. Since this heat pump is operated by proportioning the two energy sources to match the characteristics of the driving engine, the system is expected to produce cooling and heating water at high COP. This paper describes heat exchanger development in the project to develop a heat-assisted Stirling heat pump. The heat pump employs the Bayonet type heat exchangers (BHX Type I) for supplying cold and hot water and (BHX Type II) for absorbing exhaust heat from the driving engine. The heat exchanger design concepts are presented and their heat transfer and flow loss characteristics in oscillating gas flow are investigated. The main concern in the BHX Type I is an improvement of gas side heat transfer and the spirally finned tubes were applied to gas side of the heat exchanger. For the BHX Type II, internal heat transfer characteristics are the main concern. Shell-and-tube type heat exchangers are widely used in Stirling machines. However, since brazing is applied to the many tubes for their manufacturing processes, it is very difficult to change flow passages to optimize heat transfer and loss characteristics once they have been made. The challenge was to enhance heat transfer on the gas side to make a highly efficient heat exchanger with fewer parts. It is shown that the Bayonet type heat exchanger can have good performance comparable to conventional heat exchangers.

  1. Direct numerical simulations of fluid flow, heat transfer and phase changes

    SciTech Connect (OSTI)

    Juric, D.; Tryggvason, G.; Han, J.

    1997-04-01

    Direct numerical simulations of fluid flow, heat transfer, and phase changes are presented. The simulations are made possible by a recently developed finite difference/front tracking method based on the one-field formulation of the governing equations where a single set of conservation equations is written for all the phases involved. The conservation equations are solved on a fixed rectangular grid, but the phase boundaries are kept sharp by tracking them explicitly by a moving grid of lower dimension. The method is discussed and applications to boiling heat transfer and the solidification of drops colliding with a wall are shown.

  2. Remote high-temperature insulatorless heat-flux gauge

    DOE Patents [OSTI]

    Noel, Bruce W. (Espanola, NM)

    1993-01-01

    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. Remote high-temperature insulatorless heat-flux gauge

    DOE Patents [OSTI]

    Noel, B.W.

    1993-12-28

    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.

  4. High-Temperature Components for Rankine-Cycle-Based Waste Heat...

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

    Components for Rankine-Cycle-Based Waste Heat Recovery Systems on Combustion Engines High-Temperature Components for Rankine-Cycle-Based Waste Heat Recovery Systems on Combustion...

  5. New tube bundle heat transfer correlations and flow regime maps for a Once Through Steam Generator 

    E-Print Network [OSTI]

    Blanchat, Thomas Kevin

    1988-01-01

    ' . Another study on annular film ? flow boiling in a vertical channel with ofFset strip fins (geom- etry similar to tube bundles) also concludes that the transition occurs at a, value of void fraction below that for tubes . The accuracy of predicted heat... film ? flow boiling in a, vertical channel with offset strip fins (geometry similar to tube bundles) also concludes that the transition occurs at a, value of void fraction below that 1' or tubes . In ter1ns of the parameter j* defined by g Wallis...

  6. New patterns in high-speed granular flows

    E-Print Network [OSTI]

    Nicolas Brodu; Renaud Delannay; Alexandre Valance; Patrick Richard

    2015-03-04

    We report on new patterns in high-speed flows of granular materials obtained by means of extensive numerical simulations. These patterns emerge from the destabilization of unidirectional flows upon increase of mass holdup and inclination angle, and are characterized by complex internal structures including secondary flows, heterogeneous particle volume fraction, symmetry breaking and dynamically maintained order. In particular, we evidenced steady and fully developed "supported" flows, which consist of a dense core surrounded by a highly energetic granular gas. Interestingly, despite their overall diversity, these regimes are shown to obey a scaling law for the mass flow rate as a function of the mass holdup. This unique set of 3D flow regimes raises new challenges for extending the scope of current granular rheological models.

  7. Sealable stagnation flow geometries for the uniform deposition of materials and heat

    DOE Patents [OSTI]

    McCarty, Kevin F. (Livermore, CA); Kee, Robert J. (Livermore, CA); Lutz, Andrew E. (Alamo, CA); Meeks, Ellen (Livermore, CA)

    2001-01-01

    The present invention employs a constrained stagnation flow geometry apparatus to achieve the uniform deposition of materials or heat. The present invention maximizes uniform fluxes of reactant gases to flat surfaces while minimizing the use of reagents and finite dimension edge effects. This results, among other things, in large area continuous films that are uniform in thickness, composition and structure which is important in chemical vapor deposition processes such as would be used for the fabrication of semiconductors.

  8. Highly simplified lateral flow-based nucleic acid sample preparation and passive fluid flow control

    DOE Patents [OSTI]

    Cary, Robert B.

    2015-12-08

    Highly simplified lateral flow chromatographic nucleic acid sample preparation methods, devices, and integrated systems are provided for the efficient concentration of trace samples and the removal of nucleic acid amplification inhibitors. Methods for capturing and reducing inhibitors of nucleic acid amplification reactions, such as humic acid, using polyvinylpyrrolidone treated elements of the lateral flow device are also provided. Further provided are passive fluid control methods and systems for use in lateral flow assays.

  9. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    SciTech Connect (OSTI)

    Hong, Tainzhen; Liu, Xaiobing

    2009-11-01

    With the current movement toward net zero energy buildings, many technologies are promoted with emphasis on their superior energy efficiency. The variable refrigerant flow (VRF) and ground source heat pump (GSHP) systems are probably the most competitive technologies among these. However, there are few studies reporting the energy efficiency of VRF systems compared with GSHP systems. In this article, a preliminary comparison of energy efficiency between the air-source VRF and GSHP systems is presented. The computer simulation results show that GSHP system is more energy efficient than the air-source VRF system for conditioning a small office building in two selected US climates. In general, GSHP system is more energy efficient than the air-source VRV system, especially when the building has significant heating loads. For buildings with less heating loads, the GSHP system could still perform better than the air-source VRF system in terms of energy efficiency, but the resulting energy savings may be marginal.

  10. Heat extracted from the long term flow test in the Fenton Hill HDR reservoir

    SciTech Connect (OSTI)

    Kruger, Paul; Robinson, Bruce

    1994-01-20

    A long-term flow test was carried out in the Fenton Hill HDR Phase-2 reservoir for 14 months during 1992-1993 to examine the potential for supplying thermal energy at a sustained rate as a commercial demonstration of HDR technology. The test was accomplished in several segments with changes in mean flowrate due to pumping conditions. Re-test estimates of the extractable heat content above a minimum useful temperature were based on physical evidence of the size of the Fenton Hill reservoir. A numerical model was used to estimate the extent of heat extracted during the individual flow segments from the database of measured production data during the test. For a reservoir volume of 6.5x10{sup 6}m{sup 3}, the total heat content above a minimum temperature of 150{degree} C was 1.5x10{sup 15}J. For the total test period at the three sustained mean flowrates, the integrated heat extracted was 0.088x10{sup 15}J, with no discernable temperature decline of the produced fluid. The fraction of energy extracted above the abandonment temperature was 5.9%. On the basis of a constant thermal energy extraction rate, the lifetime of the reservoir (without reservoir growth) to the abandonment temperature would be 13.3 years, in good agreement with the pre-test estimate of 15.0 years for the given reservoir volume.

  11. Cross flow heat exchange of textile cellular metal core sandwich panels , T.J. Lu b,*, H.P. Hodson a

    E-Print Network [OSTI]

    Wadley, Haydn

    Cross flow heat exchange of textile cellular metal core sandwich panels J. Tian a , T.J. Lu b,*, H. Finally, the thermal performance of brazed woven tex- tiles is compared with other heat exchanger media flow resistance and heat transfer rate were measured. The flow friction factor is found to depend

  12. Lithium Mass Flow Control for High Power Lorentz Force Accelerators

    E-Print Network [OSTI]

    Lithium Mass Flow Control for High Power Lorentz Force Accelerators Andrea D. Kodys1 , Gregory Laboratory, Pasadena, CA 91109 (609).258.5220, choueiri@princeton.edu Abstract. A lithium feeding system has been developed to measure and control propellant flow for 30-200 kW Lithium Lorentz Force Accelerators

  13. High power laser heating of low absorption materials

    SciTech Connect (OSTI)

    Olson, K.; Talghader, J.; Ogloza, A.; Thomas, J.

    2014-09-28

    A model is presented and confirmed experimentally that explains the anomalous behavior observed in continuous wave (CW) excitation of thermally isolated optics. Distributed Bragg Reflector (DBR) high reflective optical thin film coatings of HfO? and SiO?were prepared with a very low absorption, about 7 ppm, measured by photothermal common-path interferometry. When illuminated with a 17 kW CW laser for 30 s, the coatings survived peak irradiances of 13 MW/cm², on 500 ?m diameter spot cross sections. The temperature profile of the optical surfaces was measured using a calibrated thermal imaging camera for illuminated spot sizes ranging from 500 ?m to 5 mm; about the same peak temperatures were recorded regardless of spot size. This phenomenon is explained by solving the heat equation for an optic of finite dimensions and taking into account the non-idealities of the experiment. An analytical result is also derived showing the relationship between millisecond pulse to CW laser operation where (1) the heating is proportional to the laser irradiance (W/m²) for millisecond pulses, (2) the heating is proportional to the beam radius (W/m) for CW, and (3) the heating is proportional to W/m? tan?¹(?(t)/m) in the transition region between the two.

  14. Shock-Wave Heating Model for Chondrule Formation: Hydrodynamic Simulation of Molten Droplets exposed to Gas Flows

    E-Print Network [OSTI]

    Hitoshi Miura; Taishi Nakamoto

    2006-11-09

    Millimeter-sized, spherical silicate grains abundant in chondritic meteorites, which are called as chondrules, are considered to be a strong evidence of the melting event of the dust particles in the protoplanetary disk. One of the most plausible scenarios is that the chondrule precursor dust particles are heated and melt in the high-velocity gas flow (shock-wave heating model). We developed the non-linear, time-dependent, and three-dimensional hydrodynamic simulation code for analyzing the dynamics of molten droplets exposed to the gas flow. We confirmed that our simulation results showed a good agreement in a linear regime with the linear solution analytically derived by Sekiya et al. (2003). We found that the non-linear terms in the hydrodynamical equations neglected by Sekiya et al. (2003) can cause the cavitation by producing negative pressure in the droplets. We discussed that the fragmentation through the cavitation is a new mechanism to determine the upper limit of chondrule sizes. We also succeeded to reproduce the fragmentation of droplets when the gas ram pressure is stronger than the effect of the surface tension. Finally, we compared the deformation of droplets in the shock-wave heating with the measured data of chondrules and suggested the importance of other effects to deform droplets, for example, the rotation of droplets. We believe that our new code is a very powerful tool to investigate the hydrodynamics of molten droplets in the framework of the shock-wave heating model and has many potentials to be applied to various problems.

  15. Experimental investigation on impingement heat transfer of gas-solid suspension flow

    SciTech Connect (OSTI)

    Yokomine, Takenhiko; Shimizu, Akihiko

    1999-07-01

    This paper aims to demonstrate experimentally the heat transfer performance of dense gas-solid suspension impinging jet for diverter cooling of the fusion power reactor. Prior to the experimental study, a tentative goal of 20 kW/m{sup 2}K was set as the heat transfer coefficient based on the expected temperature level of both coolant and diverter plate materials. Figure A-1 summarizes the results of experiments, where H/D is non-dimensional space between nozzle exit and impingement plate. The ranges of examined nozzle Reynolds number Re{sub N} and thermal loading ratio {Gamma}{sub th} were 5.5 x 10{sup 4} {<=} Re{sub N} {<=} 2.4 x 10{sup 5} and 0 {<=} {Gamma}{sub th} {<=} 8.55, respectively. When the glassy-carbon (G-C) particles with 26{micro}m in diameter were used, the maximum heat transfer coefficient could not reach the target value because the solid flow rate was restricted by the crucial erosion damage of test plate and a strong vibration observed in the test line. On the other hand, in the case that the fine graphite particles (10{micro}m in diameter) were used, the maximum heat transfer coefficient of 20 kW/m{sup 2}K was obtained at relatively dilute condition of solid loading ratio, which is considered to be due to the additive production of turbulence by particles' wake. Furthermore, the following consideration can be obtained. (1) Changing the particle from hard glassy carbon to soft and fine graphite is effective not only for anti-erosion but also for heat transfer enhancement by increasing heat capacity. (2) Turbulence augmentation by particles is also important for heat transfer enhancement in addition to the increased heat capacity. However, increasing the solid loading is likely to lead to the saturation of heat transfer enhancement effect, on the contrary, to the attenuation of turbulence. (3) If soft and fine particle, like graphite of 10{micro}m diameter employed in present study, is used as suspended particle in coolant for anti-erosion, the cooling by the gas-solid suspension impinging jet will be able to correspond to the thermal heat flux on the diverter plate when the nozzle Reynolds number is 1.5 x 10{sup 5} and thermal loading ratio is only 3. Provided that fine particles is used, however, some additional difficulties may be occurred, such as handling of powder and thermophoresis adhesion on the heat transfer surface.

  16. High energy density redox flow device

    DOE Patents [OSTI]

    Chiang, Yet-Ming; Carter, William Craig; Duduta, Mihai; Limthongkul, Pimpa

    2014-05-13

    Redox flow devices are described including a positive electrode current collector, a negative electrode current collector, and an ion-permeable membrane separating said positive and negative current collectors, positioned and arranged to define a positive electroactive zone and a negative electroactive zone; wherein at least one of said positive and negative electroactive zone comprises a flowable semi-solid composition comprising ion storage compound particles capable of taking up or releasing said ions during operation of the cell, and wherein the ion storage compound particles have a polydisperse size distribution in which the finest particles present in at least 5 vol % of the total volume, is at least a factor of 5 smaller than the largest particles present in at least 5 vol % of the total volume.

  17. Development of Micro/Nano-Scale Sensors for Investigation of Heat Transfer in Multi-Phase Flows 

    E-Print Network [OSTI]

    Jeon, Sae Il

    2012-10-19

    The objective of this investigation was to develop micro/nano-scale temperature sensors for measuring surface temperature transients in multi-phase flows and heat transfer. Surface temperature fluctuations were measured on substrates exposed...

  18. The Influence of Proposed Repository Thermal Load on Multiphase Flow and Heat Transfer in the Unsaturated Zone of Yucca Mountain

    E-Print Network [OSTI]

    Wu, Y.-S.; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, G.S.

    2006-01-01

    and Heat Flow Near Yucca Mountain, Nevada: Some Tectonic andLarge Block Test at Yucca Mountain, Nevada, Water Resourcesthe Drift Scale Test at Yucca Mountain, Nevada, Journal of

  19. Measurements of wall heat (mass) transfer for flow through blockages with round and square holes in a wide rectangular channel 

    E-Print Network [OSTI]

    Cervantes, Joel

    2002-01-01

    Naphthalene sublimation and pressure measurement experiments were conducted to study heat (mass) transfer enhancement by blockages with staggered round and square holes for turbulent air flows through the holes in the blockages in an 8:1 rectangular...

  20. Secondary heat exchanger design and comparison for advanced high temperature reactor

    SciTech Connect (OSTI)

    Sabharwall, P.; Kim, E. S.; Siahpush, A.; McKellar, M.; Patterson, M.

    2012-07-01

    Next generation nuclear reactors such as the advanced high temperature reactor (AHTR) are designed to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. This study considers two different types of heat exchangers - helical coiled heat exchanger and printed circuit heat exchanger - as possible options for the AHTR secondary heat exchangers with distributed load analysis and comparison. Comparison is provided for all different cases along with challenges and recommendations. (authors)

  1. Ultra high vacuum heating and rotating specimen stage

    DOE Patents [OSTI]

    Coombs, III, Arthur W. (Patterson, CA)

    1995-01-01

    A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1.times.10.sup.-9 torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating.

  2. Possible high power limitations from RF pulsed heating

    SciTech Connect (OSTI)

    Pritzkau, D.P.; Bowden, G.B.; Menegat, A.; Siemann, R.H. [Stanford Linear Accelerator Center, Stanford University, California 94309 (United States)

    1999-05-01

    One of the possible limitations to achieving high power in RF structures is damage to metal surfaces due to RF pulsed heating. Such damage may lead to degradation of RF performance. An experiment to study RF pulsed heating on copper has been developed at SLAC. The experiment consists of operating two pillbox cavities in the TE{sub 011} mode using a 50 MW X-Band klystron. The estimated temperature rise of the surface of copper is 350&hthinsp;{degree}C for a power input of 20 MW to each cavity with a pulse length of 1.5 {mu}s. Preliminary results from an experiment performed earlier are presented. A revised design for continued experiments is also presented along with relevant theory and calculations. {copyright} {ital 1999 American Institute of Physics.}

  3. Ultra high vacuum heating and rotating specimen stage

    DOE Patents [OSTI]

    Coombs, A.W. III

    1995-05-02

    A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1{times}10{sup {minus}9} torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating. 5 figs.

  4. Compare Energy Use in Variable Refrigerant Flow Heat Pumps Field Demonstration and Computer Model

    SciTech Connect (OSTI)

    Sharma, Chandan; Raustad, Richard

    2013-06-01

    Variable Refrigerant Flow (VRF) heat pumps are often regarded as energy efficient air-conditioning systems which offer electricity savings as well as reduction in peak electric demand while providing improved individual zone setpoint control. One of the key advantages of VRF systems is minimal duct losses which provide significant reduction in energy use and duct space. However, there is limited data available to show their actual performance in the field. Since VRF systems are increasingly gaining market share in the US, it is highly desirable to have more actual field performance data of these systems. An effort was made in this direction to monitor VRF system performance over an extended period of time in a US national lab test facility. Due to increasing demand by the energy modeling community, an empirical model to simulate VRF systems was implemented in the building simulation program EnergyPlus. This paper presents the comparison of energy consumption as measured in the national lab and as predicted by the program. For increased accuracy in the comparison, a customized weather file was created by using measured outdoor temperature and relative humidity at the test facility. Other inputs to the model included building construction, VRF system model based on lab measured performance, occupancy of the building, lighting/plug loads, and thermostat set-points etc. Infiltration model inputs were adjusted in the beginning to tune the computer model and then subsequent field measurements were compared to the simulation results. Differences between the computer model results and actual field measurements are discussed. The computer generated VRF performance closely resembled the field measurements.

  5. Numerical study on coupled fluid flow and heat transfer process in parabolic trough solar collector tube

    SciTech Connect (OSTI)

    Tao, Y.B.; He, Y.L.

    2010-10-15

    A unified two-dimensional numerical model was developed for the coupled heat transfer process in parabolic solar collector tube, which includes nature convection, forced convection, heat conduction and fluid-solid conjugate problem. The effects of Rayleigh number (Ra), tube diameter ratio and thermal conductivity of the tube wall on the heat transfer and fluid flow performance were numerically analyzed. The distributions of flow field, temperature field, local Nu and local temperature gradient were examined. The results show that when Ra is larger than 10{sup 5}, the effects of nature convection must be taken into account. With the increase of tube diameter ratio, the Nusselt number in inner tube (Nu{sub 1}) increases and the Nusselt number in annuli space (Nu{sub 2}) decreases. With the increase of tube wall thermal conductivity, Nu{sub 1} decreases and Nu{sub 2} increases. When thermal conductivity is larger than 200 W/(m K), it would have little effects on Nu and average temperatures. Due to the effect of the nature convection, along the circumferential direction (from top to down), the temperature in the cross-section decreases and the temperature gradient on inner tube surface increases at first. Then, the temperature and temperature gradients would present a converse variation at {theta} near {pi}. The local Nu on inner tube outer surface increases along circumferential direction until it reaches a maximum value then it decreases again. (author)

  6. Thermal hydraulic performance testing of printed circuit heat exchangers in a high-temperature helium test facility

    SciTech Connect (OSTI)

    Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup; Richard N. Christensen; Michael W. Patterson

    2014-04-01

    In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750–800 °C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot and 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 °C/1.0–2.7 MPa for the cold side and 208–790 °C/1.0–2.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.

  7. Shock-Wave Heating Model for Chondrule Formation: Hydrodynamic Simulation of Molten Droplets exposed to Gas Flows

    E-Print Network [OSTI]

    Miura, H; Miura, Hitoshi; Nakamoto, Taishi

    2006-01-01

    Millimeter-sized, spherical silicate grains abundant in chondritic meteorites, which are called as chondrules, are considered to be a strong evidence of the melting event of the dust particles in the protoplanetary disk. One of the most plausible scenarios is that the chondrule precursor dust particles are heated and melt in the high-velocity gas flow (shock-wave heating model). We developed the non-linear, time-dependent, and three-dimensional hydrodynamic simulation code for analyzing the dynamics of molten droplets exposed to the gas flow. We confirmed that our simulation results showed a good agreement in a linear regime with the linear solution analytically derived by Sekiya et al. (2003). We found that the non-linear terms in the hydrodynamical equations neglected by Sekiya et al. (2003) can cause the cavitation by producing negative pressure in the droplets. We discussed that the fragmentation through the cavitation is a new mechanism to determine the upper limit of chondrule sizes. We also succeeded t...

  8. Thermal studies in a geothermal area: Report I. Thermal studies at Roosevelt Hot Springs, Utah; Report II. Heat flow above an arbitrarily dipping plane of heat sources; and Report III. A datum correction for heat flow measurements made on an arbitrary surface

    SciTech Connect (OSTI)

    Wilson, W.R.; Chapman, D.S.

    1980-10-01

    Separate abstracts were prepared for the three reports included in this volume on the interpretation of heat flow data in a geothermal area. (MHR)

  9. Coupled Model for Heat and Water Transport in a High Level Waste...

    Energy Savers [EERE]

    Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt This report...

  10. Cryogenic Heat Pipe for Cooling High Temperature Superconductors with Application to

    E-Print Network [OSTI]

    Cryogenic Heat Pipe for Cooling High Temperature Superconductors with Application;#12;Cryogenic Heat Pipe for Cooling High Temperature Superconductors with Application to Electromagnetic Superconductors with Application to Electromagnetic Formation Flight Satellites by Daniel W. Kwon Submitted

  11. Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas

    SciTech Connect (OSTI)

    Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL

    2011-01-01

    Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.

  12. An analytical oscillating-flow thermal analysis of the heat exchangers and regenerator in Stirling machines

    SciTech Connect (OSTI)

    Monte, F. de; Galli, G.; Marcotullio, F.

    1996-12-31

    A closed form-expression for the effectiveness of the heat exchangers and regenerator of a Stirling cycle machine is given. This result may be used in a simple way in order to evaluate their effect on the machine performance. The proposed method, indeed, allows the actual cycle gas temperatures in the heater and cooler to be obtained readily, once the geometry of the heater, cooler and regenerator is known and some quantities characterizing the engine dynamics (strokes, frequency and phase angle of the moving elements) and its heat-exchange processes (inlet temperatures of the heating and cooling fluids, and their volumetric flow rates) are measured. Thus, an immediate indication about the effectiveness of the heat exchangers and regenerator as well as about the machine thermal efficiency may be obtained. The availability of a closed-form expression for the heater, regenerator and cooler effectiveness is useful especially for those engines, like the free-piston Stirling engines, whose design requires the application of analytically based optimization criteria.

  13. A numerical study of heat island flows in an open domain: Stationary solutions

    E-Print Network [OSTI]

    Dubois, Thierry

    2007-01-01

    We present two dimensional numerical simulations of a natural convection problem in an unbounded domain. A thermal stratification is applied in the vertical direction and the flow circulation is induced by a heat island located on the ground. For this problem, thermal perturbations are convected in the horizontal direction far from the heated element so that very elongated computational domains have to be used in order to compute accurate numerical solutions. To avoid this difficulty thermal sponge layers are added at the vertical boundaries. With this approach, stationary solutions at $Ra\\le 10^5$ are investigated. Boussinesq equations are discretized with a second-order finite volume scheme on a staggered grid combined with a second-order projection method for the time integration.

  14. Natural Refrigerant High-Performance Heat Pump for Commercial...

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

    (DE-FOA-0000823) Project Objective This project aims to develop a regenerative air source heat pump for commercial and industrial heating, ventilation, and air conditioning (HVAC)...

  15. Low and high Temperature Dual Thermoelectric Generation Waste Heat Recovery System for Light-Duty Vehicles

    Broader source: Energy.gov [DOE]

    Developing a low and high temperature dual thermoelectric generation waste heat recovery system for light-duty vehicles.

  16. Urban Sewage Delivery Heat Transfer System (1): Flow Resistance and Energy Analysis 

    E-Print Network [OSTI]

    Zhang, C.; Wu, R.; Li, G.; Li, X.; Huang, L.; Sun, D.

    2006-01-01

    , Shenzhen, China Renewable Energy Resources and a Greener Future Vol.VIII-8-4 Urban Sewage Delivery Heat Transfer System (1): Flow Resistance and Energy Analysis1 Chenghu Zhang Ronghua Wu Guitao Li Xin Li Lei Huang Dexing Sun Doctor Master...) By the numeric calculation and the simplification, the power function form, can be obtained, which is used in the engineering easily. It is 0.30 0.0235 w d? = (2) The result of (2) is slight bigger than that of (1), but the errors are within 3...

  17. Reduced heat flow in light water (H2O) due to heavy water (D2O)

    E-Print Network [OSTI]

    William R. Gorman; James D. Brownridge

    2008-09-04

    The flow of heat, from top to bottom, in a column of light water can be decreased by over 1000% with the addition of heavy water. A column of light water cools from 25 C to 0 C in 11 hours, however, with the addition of heavy water it takes more than 100 hours. There is a concentration dependence where the cooling time increases as the concentration of added (D2O) increases, with a near maximum being reached with as little as 2% of (D2O) added. This phenomenon will not occur if the water is mixed after the heavy water is added.

  18. The flow and heat transfer in a viscous fluid over an unsteady stretching surface

    E-Print Network [OSTI]

    Ene, Remus-Daniel; Marinca, Bogdan

    2015-01-01

    In this paper we have studied the flow and heat transfer in a viscous fluid by a horizontal sheet. The stretching rate and temperature of the sheet vary with time. The governing equations for momentum and thermal energy are reduced to ordinary differential equations by means of similarity transformation. These equations are solved approximately by means of the Optimal Homotopy Asymptotic Method (OHAM) which provides us with a convenient way to control the convergence of approximation solutions and adjust convergence rigorous when necessary. Some examples are given and the results obtained reveal that the proposed method is effective and easy to use.

  19. High Thermal Conductivity Polymer Composites for Low-Cost Heat...

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

    Aerospace Heat recovery at moderate temperatures Benefits Lower cost Lightweight Corrosion resistance Multifunctionality Transition and...

  20. Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Ali Siahpush; Michael McKellar; Michael Patterson; Eung Soo Kim

    2012-06-01

    The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondary heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangers—helical coiled heat exchanger and printed circuit heat exchanger—as possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.

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

    E-Print Network [OSTI]

    Konetchy, Brant Evan

    2014-12-31

    and groundwater flux. In this work, we constructed a sandbox to simulate a sand aquifer and performed a series of heat tracer tests under different flow rates. By analyzing the temperature responses among different tests, we developed a quantitative temperature...

  2. Glass Strengthening via High-Intensity Plasma-Arc Heating

    SciTech Connect (OSTI)

    Wereszczak, Andrew A; Harper, David C; Duty, Chad E; Patel, P

    2010-01-01

    The use of a high-intensity plasma-arc lamp was used to irradiate the surface of soda-lime silicate glass tiles to determine if an increase in strength could be achieved. The lamp had a power density of 3500 W/cm2, a processing area of 1 cm x 10 cm, irradiated near-infrared heating at a wavelength between 0.2 1.4 m, and was controlled to unidirectionally sweep across 50-mm-square tiles at a constant speed of 8 mm/s. Ring-on-ring (RoR) equibiaxial flexure and 4 pt uni-directional flexure testings of entire tiles were used to measure and compare failure stress distributions of treated and untreated glass. Even with non-optimized processing conditions, RoR failure stress increased by approximately 25% and the 4 pt bend failure stress increased by approximately 65%. Strengthening was due to a fire-polishing-like mechanism. The arc-lamp heat-treatment caused the location of the strength-limiting flaws in the 4-pt-bend tiles to change; namely, failure initiation occurred on the gage section surface for the treated glass whereas it occurred at a gage section edge for the untreated. Arc-lamp heat-treatment is attractive not only because it provides strengthening, but because it can (non-contact) process large amounts of glass quickly and inexpensively, and is a process that either a glass manufacturer or end-user can readily employ.

  3. Experimental and numerical study of mixed convection with flow reversal in coaxial double-duct heat exchangers

    SciTech Connect (OSTI)

    Mare, Thierry; Voicu, Ionut; Miriel, Jacques [Laboratoire de Genie Civil et de Genie Mecanique (LGCGM), INSA de Rennes, IUT Saint Malo, 35043 Rennes (France); Galanis, Nicolas [Faculte de genie, Universite de Sherbrooke, Sherbrooke, QC (Canada); Sow, Ousmane [Laboratoire d'Energie Appliquee, Ecole superieure Polytechnique, Dakar (Senegal)

    2008-04-15

    Velocity vectors in a vertical coaxial double-duct heat exchanger for parallel ascending flow of water under conditions of laminar mixed convection have been determined experimentally using the particle image velocimetry technique. The measured velocity distributions for large annular flow rates, resulting in an essentially isothermal environment for the stream in the inner tube, are in very good agreement with corresponding numerical predictions. For flow rates of the same order of magnitude in the inner tube and the annulus, and corresponding temperature differences of about 20 C, experimental observations show that flow reversal occurs simultaneously in both streams over large axial distances for both heating and cooling of the flow in the inner tube. (author)

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

    E-Print Network [OSTI]

    Shiralkar, B. S.

    1968-01-01

    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 ...

  5. Heat pipe technology development for high temperature space radiator applications

    SciTech Connect (OSTI)

    Merrigan, M.A.; Keddy, E.S.; Sena, J.T.; Elder, M.G.

    1984-01-01

    Technology requirements for heat pipe radiators, potentially among the lightest weight systems for space power applications, include flexible elements, and improved specific radiator performance(kg/kW). For these applications a flexible heat pipe capable of continuous operation through an angle of 180/sup 0/ has been demonstrated. The effect of bend angle on the heat pipe temperature distribution is reviewed. An analysis of lightweight membrane heat pipe radiators that use surface tension forces for fluid containment has been conducted. The design analysis of these lightweight heat pipes is described and a potential application in heat rejection systems for space nuclear power plants outlined.

  6. Ice flow sensitivity to geothermal heat flux of Pine Island Glacier, Antarctica

    E-Print Network [OSTI]

    Larour, E; Morlighem, M; Seroussi, H; Schiermeier, J; Rignot, E; Rignot, E

    2012-01-01

    to geothermal heat flux of Pine Island Glacier, Antarcticato geothermal heat flux of Pine Island Glacier, Antarctica,Pine Island Glacier, West Antarctica: (a) geothermal heat

  7. A Temperature-Profile Method for Estimating Flow Processes in Geologic Heat Pipes

    E-Print Network [OSTI]

    Birkholzer, Jens T.

    2004-01-01

    change and capillarity—the heat pipe effect, Int. J. Heatgeothermal reservoirs as heat pipes in fractured porousfor the radial-symmetric heat pipe system (without gravity)

  8. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    Performance of ground source heat pump system in a near-zerosimulation tool for ground- source heat pump system designflow systems and ground source heat pump systems Abstract

  9. Influence of lubricant oil on heat transfer performance of refrigerant flow boiling inside small diameter tubes. Part I: Experimental study

    SciTech Connect (OSTI)

    Wei, Wenjian; Ding, Guoliang; Hu, Haitao; Wang, Kaijian

    2007-10-15

    Two-phase flow pattern and heat transfer characteristics of refrigerant-oil mixture flow boiling inside small tubes with inside diameters of 6.34 mm and 2.50 mm are investigated experimentally. The test condition of nominal oil concentration is from 0% to 5%, mass flux from 200 to 400 kg m{sup -2} s{sup -1}, heat flux from 3.2 to 14 kW m{sup -2}, evaporation temperature of 5 C, inlet quality from 0.1 to 0.8, and quality change from 0.1 to 0.2. Wavy, wavy-annular, annular and mist-annular flow pattern in 6.34 mm tube are observed, while only slug-annular and annular flow pattern are observed in 2.50 mm tube. Oil presence can make annular flow to form early and to retard to diminish in quality direction at nominal oil concentration {>=}3%. Augmentation effect of oil on heat transfer coefficient becomes weakened or even diminishes for small diameter tube while detrimental effect of oil on small tube performance becomes more significant than large tube. For both test tubes, variation of heat transfer coefficient and enhanced factor with oil concentration is irregular. Two-phase heat transfer multiplier with refrigerant-oil mixture properties increases consistently and monotonically with local oil concentration at different vapor quality. (author)

  10. High energy density Z-pinch plasmas using flow stabilization

    SciTech Connect (OSTI)

    Shumlak, U. Golingo, R. P. Nelson, B. A. Bowers, C. A. Doty, S. A. Forbes, E. G. Hughes, M. C. Kim, B. Knecht, S. D. Lambert, K. K. Lowrie, W. Ross, M. P. Weed, J. R.

    2014-12-15

    The ZaP Flow Z-Pinch research project[1] at the University of Washington investigates the effect of sheared flows on MHD instabilities. Axially flowing Z-pinch plasmas are produced that are 100 cm long with a 1 cm radius. The plasma remains quiescent for many radial Alfvén times and axial flow times. The quiescent periods are characterized by low magnetic mode activity measured at several locations along the plasma column and by stationary visible plasma emission. Plasma evolution is modeled with high-resolution simulation codes – Mach2, WARPX, NIMROD, and HiFi. Plasma flow profiles are experimentally measured with a multi-chord ion Doppler spectrometer. A sheared flow profile is observed to be coincident with the quiescent period, and is consistent with classical plasma viscosity. Equilibrium is determined by diagnostic measurements: interferometry for density; spectroscopy for ion temperature, plasma flow, and density[2]; Thomson scattering for electron temperature; Zeeman splitting for internal magnetic field measurements[3]; and fast framing photography for global structure. Wall stabilization has been investigated computationally and experimentally by removing 70% of the surrounding conducting wall to demonstrate no change in stability behavior.[4] Experimental evidence suggests that the plasma lifetime is only limited by plasma supply and current waveform. The flow Z-pinch concept provides an approach to achieve high energy density plasmas,[5] which are large, easy to diagnose, and persist for extended durations. A new experiment, ZaP-HD, has been built to investigate this approach by separating the flow Z-pinch formation from the radial compression using a triaxial-electrode configuration. This innovation allows more detailed investigations of the sheared flow stabilizing effect, and it allows compression to much higher densities than previously achieved on ZaP by reducing the linear density and increasing the pinch current. Experimental results and scaling analyses will be presented. In addition to studying fundamental plasma science and high energy density physics, the ZaP and ZaP-HD experiments can be applied to laboratory astrophysics.

  11. Process Heat Exchanger Options for the Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-06-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  12. Process Heat Exchanger Options for Fluoride Salt High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-04-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  13. Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow

    E-Print Network [OSTI]

    Witten, Thomas A.

    Gravity Surface Wave Bifurcation in a Highly Turbulent Swirling Flow Michael Baumer University Gravity Wave 2 3 Measurements 3 4 Mechanical Hardware: Problems and Solutions 5 5 Results 7 6 Conclusions investigated a free-surface gravity wave bifurcation in the large-separation regime, that is, where

  14. Fuel Cell Assembly Process Flow for High Productivity

    E-Print Network [OSTI]

    Edwards, David A.

    Fuel Cell Assembly Process Flow for High Productivity Problem Presenter Ram Ramanan Bloom Energy: Introduction Bloom Energy manufactures power modules based on fuel cell technology. These are built up their possible placement within a cell assembly. Currently, these rules for assembling the basic components

  15. High Temperature Fuel Cell Tri-Generation of Power, Heat & H2...

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

    Heat & H2 from Biogas High Temperature Fuel Cell Tri-Generation of Power, Heat & H2 from Biogas Success story about using waste water treatment gas for hydrogen production at UC...

  16. Estimation of the local heat-transfer coefficient in the laminar flow regime in coiled tubes by the Tikhonov regularisation method

    E-Print Network [OSTI]

    Bazán, Fermín S. V.

    Estimation of the local heat-transfer coefficient in the laminar flow regime in coiled tubes February 2014 Keywords: Heat-transfer enhancement Coiled tubes Local convective heat-flux estimation. Although many authors have investigated the forced convective heat transfer in coiled tubes, most of them

  17. Modeling Free Convection Flow of Liquid Hydrogen within a Cylindrical Heat Exchanger Cooled to 14 K

    E-Print Network [OSTI]

    Yang, S.W.; Oxford U.

    2004-01-01

    is to put part of the heat exchange surface inside thewall as well as added heat exchange surface. This study

  18. Co-flow anode/cathode supply heat exchanger for a solid-oxide fuel cell assembly

    DOE Patents [OSTI]

    Haltiner, Jr., Karl J.; Kelly, Sean M.

    2005-11-22

    In a solid-oxide fuel cell assembly, a co-flow heat exchanger is provided in the flow paths of the reformate gas and the cathode air ahead of the fuel cell stack, the reformate gas being on one side of the exchanger and the cathode air being on the other. The reformate gas is at a substantially higher temperature than is desired in the stack, and the cathode gas is substantially cooler than desired. In the co-flow heat exchanger, the temperatures of the reformate and cathode streams converge to nearly the same temperature at the outlet of the exchanger. Preferably, the heat exchanger is formed within an integrated component manifold (ICM) for a solid-oxide fuel cell assembly.

  19. Optimal homotopy perturbation method for nonlinear differential equations governing MHD Jeffery-Hamel flow with heat transfer problem

    E-Print Network [OSTI]

    Marinca, Vasile

    2015-01-01

    In this paper, Optimal Homotopy Perturbation Method (OHPM) is employed to determine an analytic approximate solutions for nonlinear MHD Jeffery-Hamel flow and heat transfer problem. The Navier-Stokes equations, taking into account Maxwell's electromagnetism and heat transfer lead to two nonlinear ordinary differential equations. The obtained results by means of OHPM show a very good agreement in comparison with the numerical results and with Homotopy Perturbation Method (HPM).

  20. Laminated metal composite formed from low flow stress layers and high flow stress layers using flow constraining elements and making same

    DOE Patents [OSTI]

    Syn, C.K.; Lesuer, D.R.

    1995-07-04

    A laminated metal composite of low flow stress layers and high flow stress layers is described which is formed using flow constraining elements, preferably in the shape of rings, individually placed around each of the low flow stress layers while pressure is applied to the stack to bond the layers of the composite together, to thereby restrain the flow of the low flow stress layers from the stack during the bonding. The laminated metal composite of the invention is made by the steps of forming a stack of alternate layers of low flow stress layers and high flow stress layers with each layer of low flow stress material surrounded by an individual flow constraining element, such as a ring, and then applying pressure to the top and bottom surfaces of the resulting stack to bond the dissimilar layers together, for example, by compression rolling the stack. In a preferred embodiment, the individual flow constraining elements surrounding the layers of low flow stress material are formed of a material which may either be the same material as the material comprising the high flow stress layers, or have similar flow stress characteristics to the material comprising the high flow stress layers. Additional sacrificial layers may be added to the top and bottom of the stack to avoid damage to the stack during the bonding step; and these additional layers may then be removed after the bonding step. 5 figs.

  1. Laminated metal composite formed from low flow stress layers and high flow stress layers using flow constraining elements and making same

    DOE Patents [OSTI]

    Syn, Chol K. (Moraga, CA); Lesuer, Donald R. (Livermore, CA)

    1995-01-01

    A laminated metal composite of low flow stress layers and high flow stress layers is described which is formed using flow constraining elements, preferably in the shape of rings, individually placed around each of the low flow stress layers while pressure is applied to the stack to bond the layers of the composite together, to thereby restrain the flow of the low flow stress layers from the stack during the bonding. The laminated metal composite of the invention is made by the steps of forming a stack of alternate layers of low flow stress layers and high flow stress layers with each layer of low flow stress material surrounded by an individual flow constraining element, such as a ring, and then applying pressure to the top and bottom surfaces of the resulting stack to bond the dissimilar layers together, for example, by compression rolling the stack. In a preferred embodiment, the individual flow constraining elements surrounding the layers of low flow stress material are formed of a material which may either be the same material as the material comprising the high flow stress layers, or have similar flow stress characteristics to the material comprising the high flow stress layers. Additional sacrificial layers may be added to the top and bottom of the stack to avoid damage to the stack during the bonding step; and these additional layers may then be removed after the bonding step.

  2. Heat flow and subsurface temperature distributions in central and western New York. Final report

    SciTech Connect (OSTI)

    Hodge, D.S.; Fromm, K.

    1984-01-01

    Initiation of a geothermal energy program in western and central New York requires knowledge of subsurface temperatures for targeting areas of potential resources. The temperature distribution in possible geothermal reservoirs, calculated from heat flow measurements and modeling techniques, shows that a large area of New York can be considered for exploitation of geothermal resources. Though the temperatures at currently accessible depths show the availability of only a low-temperature (less than 100/sup 0/C), direct-use resource, this can be considered as an alternative for the future energy needs of New York State. From analysis of bottom-hole-temperature data and direct heat flow measurements, estimates of temperatures in the Cambrian Sandstones provide the basis of the economic evaluation of the reservoir. This reservoir contains the extractable fluids needed for targeting a potential geothermal well site in the low-temperature geothermal target zone. In the northern section of the Appalachian basin, reservoir temperatures in the Cambrian are below 50/sup 0/C but may be over 80/sup 0/C in the deeper parts of the basin in southern New York State. Using a minimum of 50/sup 0/C as a useful reservoir temperature, temperatures in excess of this value are encountered in the Theresa Formation at depths in excess of 1300 meters. Considering a maximum depth for economical drilling to be 2500 meters with present technology, the 2500 meters to the Theresa (sea level datum) forms the lower limit of the geothermal resource. Temperatures in the range of 70/sup 0/C to 80/sup 0/C are predicted for the southern portion of New York State.

  3. A parametric study of shock jump chemistry, electron temperature, and radiative heat transfer models in hypersonic flows 

    E-Print Network [OSTI]

    Greendyke, Robert Brian

    1988-01-01

    will examine the radiance model and various step models in order to determine their appropriateness to the flight regime of the AOTV. The final area to be investigated will be the effect of nonequilibrium corrections on the radiative heat transfer models... of T and e T will be valid as long as there is a reasonable amount vNs of nitrogen molecules in the flow. Radiative Heat Transfer Models For this study, four radiative heat transfer models were examined. One of these models is an optically thin radiance...

  4. UNSAT-H Version 2. 0: Unsaturated soil water and heat flow model

    SciTech Connect (OSTI)

    Fayer, M.J.; Jones, T.L.

    1990-04-01

    This report documents UNSAT-H Version 2.0, a model for calculating water and heat flow in unsaturated media. The documentation includes the bases for the conceptual model and its numerical implementation, benchmark test cases, example simulations involving layered soils and plant transpiration, and the code listing. Waste management practices at the Hanford Site have included disposal of low-level wastes by near-surface burial. Predicting the future long-term performance of any such burial site in terms of migration of contaminants requires a model capable of simulating water flow in the unsaturated soils above the buried waste. The model currently used to meet this need is UNSAT-H. This model was developed at Pacific Northwest Laboratory to assess water dynamics of near-surface, waste-disposal sites at the Hanford Site. The code is primarily used to predict deep drainage as a function of such environmental conditions as climate, soil type, and vegetation. UNSAT-H is also used to simulate the effects of various practices to enhance isolation of wastes. 66 refs., 29 figs., 7 tabs.

  5. High-Performance Refrigerator Using Novel Rotating Heat Exchanger...

    Energy Savers [EERE]

    Cooler relative to current heat exchanger technology are additional refrigerated space, noise reduction, and fouling reduction. Additional refrigerated volume realized by the more...

  6. Influence of lubricant oil on heat transfer performance of refrigerant flow boiling inside small diameter tubes. Part II: Correlations

    SciTech Connect (OSTI)

    Wei, Wenjian; Ding, Guoliang; Hu, Haitao; Wang, Kaijian

    2007-10-15

    The predictive ability of the available state-of-the-art heat transfer correlations of refrigerant-oil mixture is evaluated with the present experiment data of small tubes with inside diameter of 6.34 mm and 2.50 mm. Most of these correlations can be used to predict the heat transfer coefficient of 6.34 mm tube, but none of them can predict heat transfer coefficient of 2.50 mm tube satisfactorily. A new correlation of two-phase heat transfer multiplier with local properties of refrigerant-oil mixture is developed. This correlation approaches the actual physical mechanism of flow boiling heat transfer of refrigerant-oil mixture and can reflect the actual co-existing conditions of refrigerant and lubricant oil. More than 90% of the experiment data of both test tubes have less than {+-}20% deviation from the prediction values of the new correlations. (author)

  7. Differential heating: A versatile method for thermal conductivity measurements in high-energy-density matter

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

    Ping, Y.; Fernandez-Panella, A.; Sio, H.; Correa, A.; Shepherd, R.; Landen, O.; London, R. A.; Sterne, P. A.; Whitley, H. D.; Fratanduono, D.; et al

    2015-09-04

    We propose a method for thermal conductivity measurements of high energy density matter based on differential heating. A temperature gradient is created either by surface heating of one material or at an interface between two materials by different energy deposition. The subsequent heat conduction across the temperature gradient is observed by various time-resolved probing techniques. Conceptual designs of such measurements using laser heating, proton heating, and x-ray heating are presented. As a result, the sensitivity of the measurements to thermal conductivity is confirmed by simulations.

  8. Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone

    E-Print Network [OSTI]

    Yakovlev, Vadim

    Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone Shawn M (electromagnetic and thermal) modeling to cover practically valuable scenarios of hybrid (heat radiation is applied to the process of hybrid heating of cylindrical samples of limestone in Ceralink's MAT TM kiln

  9. Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped Emmanuel Rousseau

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped silicon the role of surface plasmons for nanoscale radiative heat transfer between doped silicon surfaces. We derive a new accurate and closed-form expression of the radiative near- field heat transfer. We also

  10. 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

  11. Heat release effects on decaying homogeneous compressible turbulence 

    E-Print Network [OSTI]

    Lee, Kurn Chul

    2009-05-15

    High Mach-number compressible flows with heat release are inherently more complicated than incompressible flows due to, among other reasons, the activation of the thermal energy mode. Such flow fields can experience significant fluctuations...

  12. Improved understanding and control of high-speed jet interaction flows 

    E-Print Network [OSTI]

    Srinivasan, Ravichandra

    2006-04-12

    A numerical study of the flow field generated by injection through diamondshaped orifices into a high-speed flow is presented in this document. Jet interaction flows have a wide range of applications in the field of engineering. These applications...

  13. TOUGH Simulations of the Updegraff's Set of Fluid and Heat Flow Problems

    E-Print Network [OSTI]

    Moridis, G.J.

    2010-01-01

    A schematic of the heat pipe problem (from Updegraff [1989])19. A schematic of the heat pipe problem (from Updegraff[Problem No.5. START Heat pipe problem - Udell and Fitch (

  14. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    tool for geothermal water loop heat pump systems, 9thInternational IEA Heat Pump Conference, Zürich, Switzerland,of ground source heat pump system in a near-zero energy

  15. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    tool for geothermal water loop heat pump systems, 9thInternational IEA Heat Pump Conference, Zürich, Switzerland,Performance of ground source heat pump system in a near-zero

  16. Electron heat flow in the solar corona: Implications of non-Maxwellian velocity distributions, the solar gravitational

    E-Print Network [OSTI]

    Scudder, Jack

    Electron heat flow in the solar corona: Implications of non-Maxwellian velocity distributions, the solar gravitational field, and Coulomb collisions John C. Dorelli Space and Atmospheric Science Group, Los Alamos National Laboratory, Los Alamos, New Mexico, USA Jack D. Scudder Department of Physics

  17. 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.

    2011-01-19

    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.

  18. 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

    2009-01-01

    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 ...

  19. High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns 

    E-Print Network [OSTI]

    Wisz, M. W.; Antonelli, R.; Ragi, E. G.

    1981-01-01

    exchangers and distillation trays permits additional energy savings by lower reboiler temperature differences, and reduced reflux requirements for a fixed column height, due to closer tray spacings. This paper surveys the heat pump systems currently...

  20. Geothermal Resource/Reservoir Investigations Based on Heat Flow and Thermal Gradient Data for the United States

    SciTech Connect (OSTI)

    D. D. Blackwell; K. W. Wisian; M. C. Richards; J. L. Steele

    2000-04-01

    Several activities related to geothermal resources in the western United States are described in this report. A database of geothermal site-specific thermal gradient and heat flow results from individual exploration wells in the western US has been assembled. Extensive temperature gradient and heat flow exploration data from the active exploration of the 1970's and 1980's were collected, compiled, and synthesized, emphasizing previously unavailable company data. Examples of the use and applications of the database are described. The database and results are available on the world wide web. In this report numerical models are used to establish basic qualitative relationships between structure, heat input, and permeability distribution, and the resulting geothermal system. A series of steady state, two-dimensional numerical models evaluate the effect of permeability and structural variations on an idealized, generic Basin and Range geothermal system and the results are described.

  1. High Efficiency R-744 Commercial Heat Pump Water Heaters

    SciTech Connect (OSTI)

    Elbel, Dr. Stefan W.; Petersen, Michael

    2013-04-25

    The project investigated the development and improvement process of a R744 (CO2) commercial heat pump water heater (HPWH) package of approximately 35 kW. The improvement process covered all main components of the system. More specific the heat exchangers (Internal heat exchanger, Evaporator, Gas cooler) as well as the expansion device and the compressor were investigated. In addition, a comparison to a commercially available baseline R134a unit of the same capacity and footprint was made in order to compare performance as well as package size reduction potential.

  2. Nonlinear convection stagnation point heat transfer and MHD fluid flow in porous medium towards a permeable shrinking sheet

    E-Print Network [OSTI]

    Kumar, Rakesh

    2015-01-01

    This investigation deals with the analysis of stagnation point heat transfer and corresponding flow features of hydromagnetic viscous incompressible fluid over a vertical shrinking sheet. The considered sheet is assumed to be permeable and subject to addition of stagnation point to control the generated vorticity in the boundary layer. The sheet is placed on the right side of the fluid saturated porous medium which is having permeability of specified form. Nonlinear convection waves in the flow field are realized due to the envisaged nonlinear relation between density and temperature. The equations governing the nonlinear convection boundary layer flow are modeled and simplified using similarity transformations. The economized equations are solved for numerical solutions by employing the implicit finite difference scheme also known as Keller-box method. The influence of the associated parameters of the problem on velocity and temperature distributions, skin friction and rate of heat transfer are presented thr...

  3. High-Heat Flux Testing of Irradiated Tungsten based Materials for Fusion Applications using Infrared Plasma Arc Lamps

    SciTech Connect (OSTI)

    Sabau, Adrian S; Ohriner, Evan Keith; Kiggans Jr, James O; Schaich, Charles Ross; Ueda, Yoshio; Harper, David C; Katoh, Yutai; Snead, Lance Lewis; Byun, Thak Sang

    2014-01-01

    Testing of advanced materials and component mock-ups under prototypical fusion high-heat flux conditions, while historically a mainstay of fusion research has proved challenging, especially for irradiated materials. A new high-heat flux testing facility based on water-wall Plasma Arc Lamps (PALs) is now being used for materials and small component testing. Two PAL systems, utilizing a 12,000 C plasma arc contained in a quartz tube cooled by a spiral water flow over the inside tube surface, are currently in use. The first PAL system provides a maximum incident heat flux of 4.2 MW/m2 over an area of 9x12 cm2. The second PAL available at ORNL provides a maximum incident heat flux of 27 MW/m2 over an area of 1x10 cm2. The absorbed heat fluxes into a tungsten target for the two PALs are approximately 1.97 and 12.7 MW/m2, respectively. This paper will present the overall design of the new PAL facilities as well as the design and implementation of the Irradiated Material Target Station (IMTS). The IMTS is primarily designed for testing the effects of heat flux or thermal cycling on material coupons of interested, such as those for plasma facing components. Moreover, IMTS designs are underway to extend the testing of small mock-ups for assessing the combined heating and thermomechanical effects of cooled, irradiated components. For the testing of material coupons , the specimens are placed in a shallow recess within the molybdenum holder that is attached to a water-cooled copper alloy rod. As the measurement of the specimen temperature for PAL is historically challenging since traditional approaches of temperature measurement cannot be employed due to the infrared heating and proximity of the PAL reflector to the specimen that does not allow a direct line of site, experiments for temperature calibration are presented. Finally, results for the high-heat flux testing of tungsten-based materials using the PAL are presented. As a demonstration of the system, results will be shown of thermal fatigue and high-heat flux testing of tungsten coupon specimens that were neutron irradiated in the HFIR reactor to neutron dose consistent to ITER lifetime.

  4. Electrically Heated High Temperature Incineration of Air Toxics 

    E-Print Network [OSTI]

    Agardy, F. J.; Wilcox, J. B.

    1990-01-01

    In-Process Technology has placed a prototype of its patented, electrically heated, packed-bed air toxics oxidizer at a northern California chemical plant. This thermal oxidizer is capable of handling a wide range of chlorinated and non...

  5. Transient Thermal, Hydraulic, and Mechanical Analysis of a Counter Flow Offset Strip Fin Intermediate Heat Exchanger using an Effective Porous Media Approach

    E-Print Network [OSTI]

    Urquiza, Eugenio

    2009-01-01

    intermediate heat exchanger used high pressure helium not asexchanger performance: predictive model for heat transfer and pressurePressure Drop Correlations for the Rectangular Offset Strip Fin Compact Heat Exchanger. ”

  6. Ly? heating of inhomogeneous high-redshift intergalactic medium

    SciTech Connect (OSTI)

    Oklop?i?, Antonija; Hirata, Christopher M., E-mail: oklopcic@astro.caltech.edu [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

    2013-12-20

    The intergalactic medium (IGM) prior to the epoch of reionization consists mostly of neutral hydrogen gas. Lyman-? (Ly?) photons produced by early stars resonantly scatter off hydrogen atoms, causing energy exchange between the radiation field and the gas. This interaction results in moderate heating of the gas due to the recoil of the atoms upon scattering, which is of great interest for future studies of the pre-reionization IGM in the H I 21 cm line. We investigate the effect of this Ly? heating in the IGM with linear density, temperature, and velocity perturbations. Perturbations smaller than the diffusion length of photons could be damped due to heat conduction by Ly? photons. The scale at which damping occurs and the strength of this effect depend on various properties of the gas, the flux of Ly? photons, and the way in which photon frequencies are redistributed upon scattering. To find the relevant length scale and the extent to which Ly? heating affects perturbations, we calculate the gas heating rates by numerically solving linearized Boltzmann equations in which scattering is treated by the Fokker-Planck approximation. We find that (1) perturbations add a small correction to the gas heating rate, and (2) the damping of temperature perturbations occurs at scales with comoving wavenumber k ? 10{sup 4} Mpc{sup –1}, which are much smaller than the Jeans scale and thus unlikely to substantially affect the observed 21 cm signal.

  7. Experimental studies on heat transfer and friction factor characteristics of laminar flow through a circular tube fitted with regularly spaced helical screw-tape inserts

    SciTech Connect (OSTI)

    Sivashanmugam, P.; Suresh, S. [Department of Chemical Engineering, National Institute of Technology, Tiruchirappalli 620 015, Tamil Nadu (India)

    2007-02-15

    Experimental investigation of heat transfer and friction factor characteristics of circular tube fitted with full-length helical screw element of different twist ratio, and helical screw inserts with spacer length 100, 200, 300 and 400mm have been studied with uniform heat flux under laminar flow condition. The experimental data obtained are verified with those obtained from plain tube published data. The effect of spacer length on heat transfer augmentation and friction factor, and the effect of twist ratio on heat transfer augmentation and friction factor have been presented separately. The decrease in Nusselt number for the helical twist with spacer length is within 10% for each subsequent 100mm increase in spacer length. The decrease in friction factor is nearly two times lower than the full length helical twist at low Reynolds number, and four times lower than the full length helical twist at high Reynolds number for all twist ratio. The regularly spaced helical screw inserts can safely be used for heat transfer augmentation without much increase in pressure drop than full length helical screw inserts. (author)

  8. Simulation of a High Efficiency Multi-bed Adsorption Heat Pump

    SciTech Connect (OSTI)

    TeGrotenhuis, Ward E.; Humble, Paul H.; Sweeney, J. B.

    2012-05-01

    Attaining high energy efficiency with adsorption heat pumps is challenging due to thermodynamic losses that occur when the sorbent beds are thermally cycled without effective heat recuperation. The multi-bed concept described here effectively transfers heat from beds being cooled to beds being heated, which enables high efficiency in thermally driven heat pumps. A simplified lumped-parameter model and detailed finite element analysis are used to simulate the performance of an ammonia-carbon sorption compressor, which is used to project the overall heat pump coefficient of performance. The effects of bed geometry and number of beds on system performance are explored, and the majority of the performance benefit is obtained with four beds. Results indicate that a COP of 1.24 based on heat input is feasible at AHRI standard test conditions for residential HVAC equipment. When compared on a basis of primary energy input, performance equivalent to SEER 13 or 14 are theoretically attainable with this system.

  9. An experimental study of convective heat transfer with microencapsulated phase change material suspension: Laminar flow in a circular tube under constant heat flux

    SciTech Connect (OSTI)

    Chen, Binjiao; Wang, Xin; Zeng, Ruolang; Zhang, Yinping; Di, Hongfa [Department of Building Science, Tsinghua University, Beijing 100084 (China); Wang, Xichun; Niu, Jianlei [Department of Building Service Engineering, The Hong Kong Polytechnic University, Hong Kong (China); Li, Yi [Institute of Textiles and Clothing, The Hong Kong Polytechnic University, Hong Kong (China)

    2008-09-15

    By contrast with the conventional heat transfer fluid (water), the microencapsulated phase change material (MPCM) suspension, with a small temperature difference between storing and releasing heat, is of much larger apparent specific heat and much higher thermal energy storage capacity. It has been suggested to serve as a dual-functional medium for thermal energy transport and/or storage. The heat transfer characteristics of a kind of MPCM suspension, formed by microencapsulating industrial-grade 1-bromohexadecane (C{sub 16}H{sub 33}Br) as phase change material, were experimentally studied for laminar flow in a circular tube under constant heat flux. A new expression of Ste is put forward in the paper, according to the physical definition of Stefan number. The results in the experiments show: (a) the dimensionless internal wall temperature of the MPCM suspension is lower than pure water, and the decrease can be up to 30% of that of water; (b) the heat transfer enhancement ratio can be 1.42 times of that of water at x{sup +} = 4.2 x 10{sup -2} for 15.8 wt% MPCM suspension, which is not as much as in some references; and (c) the pump consumption of the MPCM suspension system decrease greatly for the larger heat transfer rate compared with water, due to phase change, the decrease can be up to 67.5% of that of water at q = 750 W (15.8 wt%). The kind of MPCM suspension has good application feasibility in practice. (author)

  10. Liquid Salts as Media for Process Heat Transfer from VHTR's: Forced Convective Channel Flow Thermal Hydraulics, Materials, and Coating

    SciTech Connect (OSTI)

    Sridharan, Kumar; Anderson, Mark; Allen, Todd; Corradini, Michael

    2012-01-30

    The goal of this NERI project was to perform research on high temperature fluoride and chloride molten salts towards the long-term goal of using these salts for transferring process heat from high temperature nuclear reactor to operation of hydrogen production and chemical plants. Specifically, the research focuses on corrosion of materials in molten salts, which continues to be one of the most significant challenges in molten salts systems. Based on the earlier work performed at ORNL on salt properties for heat transfer applications, a eutectic fluoride salt FLiNaK (46.5% LiF-11.5%NaF-42.0%KF, mol.%) and a eutectic chloride salt (32%MgCl2-68%KCl, mole %) were selected for this study. Several high temperature candidate Fe-Ni-Cr and Ni-Cr alloys: Hastelloy-N, Hastelloy-X, Haynes-230, Inconel-617, and Incoloy-800H, were exposed to molten FLiNaK with the goal of understanding corrosion mechanisms and ranking these alloys for their suitability for molten fluoride salt heat exchanger and thermal storage applications. The tests were performed at 850��������C for 500 h in sealed graphite crucibles under an argon cover gas. Corrosion was noted to occur predominantly from dealloying of Cr from the alloys, an effect that was particularly pronounced at the grain boundaries Alloy weight-loss due to molten fluoride salt exposure correlated with the initial Cr-content of the alloys, and was consistent with the Cr-content measured in the salts after corrosion tests. The alloys���¢�������� weight-loss was also found to correlate to the concentration of carbon present for the nominally 20% Cr containing alloys, due to the formation of chromium carbide phases at the grain boundaries. Experiments involving molten salt exposures of Incoloy-800H in Incoloy-800H crucibles under an argon cover gas showed a significantly lower corrosion for this alloy than when tested in a graphite crucible. Graphite significantly accelerated alloy corrosion due to the reduction of Cr from solution by graphite and formation on Cr-carbide on the graphite surface. Ni-electroplating dramatically reduced corrosion of alloys, although some diffusion of Fe and Cr were observed occur through the Ni plating. A pyrolytic carbon and SiC (PyC/SiC) CVD coating was also investigated and found to be effective in mitigating corrosion. The KCl-MgCl2 molten salt was less corrosive than FLiNaK fluoride salts for corrosion tests performed at 850oC. Cr dissolution in the molten chloride salt was still observed and consequently Ni-201 and Hastelloy N exhibited the least depth of attack. Grain-boundary engineering (GBE) of Incoloy 800H improved the corrosion resistance (as measured by weight loss and maximum depth of attack) by nearly 50% as compared to the as-received Incoloy 800H sample. Because Cr dissolution is an important mechanism of corrosion, molten salt electrochemistry experiments were initiated. These experiments were performed using anodic stripping voltammetry (ASV). Using this technique, the reduction potential of Cr was determined against a Pt quasi-reference electrode as well as against a Ni(II)-Ni reference electrode in molten FLiNaK at 650 oC. The integrated current increased linearly with Cr-content in the salt, providing for a direct assessment of the Cr concentration in a given salt of unknown Cr concentration. To study heat transfer mechanisms in these molten salts over the forced and mixed convection regimes, a forced convective loop was constructed to measure heat transfer coefficients, friction factors and corrosion rates in different diameter tubes in a vertical up flow configuration in the laminar flow regime. Equipment and instrumentation for the forced convective loop was designed, constructed, and tested. These include a high temperature centrifugal pump, mass flow meter, and differential pressure sensing capabilities to an uncertainty of < 2 Pa. The heat transfer coefficient for the KCl-MgCl2 salt was measured in t

  11. DEVELOPING FLOW AND HEAT TRANSFER IN STRONGLY CURVED DUCTS OF RECTANGULAR CROSS-SECTION

    E-Print Network [OSTI]

    Yee, G.

    2010-01-01

    123. HUMPHREY, J.A.C. , "Flow in Ducts with Curvature andViscous Flow in Curved Ducts of Rectangular Cross-Sections,"Laminar Flow in a Square Duct of Strong Curvature,1I J.

  12. Simulated heat storage in a perennially ice-covered high Arctic lake: Sensitivity to climate change

    E-Print Network [OSTI]

    Vincent, Warwick F.

    . In contrast, the perennially ice-covered lakes found at high latitudes can store heat in excess of the annualSimulated heat storage in a perennially ice-covered high Arctic lake: Sensitivity to climate change conductivity and temperature profiles. They are salinity stratified and have deep thermal maxima that persist

  13. Alternatives Generation and Analysis for Heat Removal from High Level Waste Tanks

    SciTech Connect (OSTI)

    WILLIS, W.L.

    2000-06-15

    This document addresses the preferred combination of design and operational configurations to provide heat removal from high-level waste tanks during Phase 1 waste feed delivery to prevent the waste temperature from exceeding tank safety requirement limits. An interim decision for the preferred method to remove the heat from the high-level waste tanks during waste feed delivery operations is presented herein.

  14. DNS of heat transfer in a transitional channel flow accompanied by a turbulent puff-like structure

    E-Print Network [OSTI]

    Tsukahara, Takahiro

    2014-01-01

    Direct numerical simulations of turbulent heat transfer in fully-developed channel flows have been performed in a range of friction Reynolds number between 60 and 180, based on the friction velocity and the channel half width $\\delta$, with emphasis on a puff-like structure, large-scale spatial intermittency. For the Reynolds numbers lower than 80 with a large computational domain of 51.2 x 2 x 22.5, the turbulent puff was observed and its significant influences on the momentum and heat transports were found. The spatial structure of the equilibrium puff, or the localized turbulence, was examined with taking account of two different thermal boundary conditions: the uniform heat-flux heating and the constant temperature difference between the walls. It was revealed that there existed a localized strong turbulent region in the form of an oblique band, along which a spanwise secondary flow was induced. In consequence, at the present lowest Reynolds number as low as 60, the flow remained turbulent and the larger ...

  15. NUCLEAR FLUID DYNAMICS VERSUS INTRANUCLEAR CASCADE--POSSIBLE EVIDENCE FOR COLLECTIVE FLOW IN CENTRAL HIGH ENERGY NUCLEAR COLLISIONS

    E-Print Network [OSTI]

    Stocker, H.

    2012-01-01

    Flow in Central High Energy Nuclear Collisions H. Stockera,under Contract High energy nuclear collisions offer a uniquesidewards flow·in high-energy nuclear collisions. The

  16. Changes in Hepatic Blood Flow During Transcatheter Arterial Infusion with Heated Saline in Hepatic VX2 Tumor

    SciTech Connect (OSTI)

    Cao Wei; Li Jing; Wu Zhiqun; Zhou Changxi; Liu Xi; Wan Yi; Duan Yunyou

    2013-06-15

    Purpose. This study evaluates the influence of transcatheter arterial infusion with heated saline on hepatic arterial and portal venous blood flows to tumor and normal hepatic tissues in a rabbit VX2 tumor model. Methods. All animal experiments were approved by the institutional animal care and use committee. Twenty rabbits with VX2 liver tumors were divided into the following two groups: (a) the treated group (n = 10), which received a 60 mL transarterial injection of 60 Degree-Sign C saline via the hepatic artery; (b) the control group (n = 10), which received a 60 mL injection of 37 Degree-Sign C saline via the hepatic artery. Using ultrasonography, the blood flows in both the portal vein and hepatic artery were measured, and the changes in the hemodynamic indices were recorded before and immediately after the injection. The changes in the tumor and normal liver tissues of the two groups were histopathologically examined by hematoxylin and eosin staining after the injection. Results. After the transcatheter arterial heated infusion, there was a decrease in the hepatic arterial blood flow to the tumor tissue, a significant decrease in the hepatic artery mean velocity (P < 0.05), and a significant increase in the resistance index (P < 0.05). On hematoxylin and eosin staining, there were no obvious signs of tissue destruction in the normal liver tissue or the tumor tissue after heated perfusion, and coagulated blood plasma was observed in the cavities of intratumoral blood vessels in the treated group. Conclusions. The changes in tumor blood flow in the rabbit VX2 tumor model were presumably caused by microthrombi in the tumor vessels, and the portal vein likely mediated the heat loss in normal liver tissue during the transarterial heated infusion.

  17. High Water Heating Bills on Lockdown at Idaho Jail

    Broader source: Energy.gov [DOE]

    Using funds from the American Recovery and Reinvestment Act, the county is installing a solar thermal hot water system that will provide nearly 70 percent of the power required for heating 600,000 gallons of water for the jail annually.

  18. High speed flow cytometer droplet formation system and method

    DOE Patents [OSTI]

    Van den Engh, Ger (Seattle, WA)

    2000-01-01

    A droplet forming flow cytometer system allows high speed processing without the need for high oscillator drive powers through the inclusion of an oscillator or piezoelectric crystal such as within the nozzle volume or otherwise unidirectionally coupled to the sheath fluid. The nozzle container continuously converges so as to amplify unidirectional oscillations which are transmitted as pressure waves through the nozzle volume to the nozzle exit so as to form droplets from the fluid jet. The oscillator is directionally isolated so as to avoid moving the entire nozzle container so as to create only pressure waves within the sheath fluid. A variation in substance concentration is achieved through a movable substance introduction port which is positioned within a convergence zone to vary the relative concentration of substance to sheath fluid while still maintaining optimal laminar flow conditions. This variation may be automatically controlled through a sensor and controller configuration. A replaceable tip design is also provided whereby the ceramic nozzle tip is positioned within an edge insert in the nozzle body so as to smoothly transition from nozzle body to nozzle tip. The nozzle tip is sealed against its outer surface to the nozzle body so it may be removable for cleaning or replacement.

  19. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, L.D.

    1987-02-11

    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.

  20. Rotary magnetic heat pump

    DOE Patents [OSTI]

    Kirol, Lance D. (Shelly, ID)

    1988-01-01

    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.

  1. Analytical and Numerical Study of Joule Heating Effects on Electrokinetically Pumped Continuous Flow PCR Chips

    E-Print Network [OSTI]

    Le Roy, Robert J.

    Analytical and Numerical Study of Joule Heating Effects on Electrokinetically Pumped Continuous, and the potential for integration.1-3 Joule heating is inevitable when electrokinetic pumping is used Form: December 8, 2007 Joule heating is an inevitable phenomenon for microfluidic chips involving

  2. High current multicharged metal ion source using high power gyrotron heating of vacuum arc plasma

    SciTech Connect (OSTI)

    Vodopyanov, A. V.; Golubev, S. V.; Khizhnyak, V. I.; Mansfeld, D. A.; Nikolaev, A. G.; Oks, E. M.; Savkin, K. P.; Vizir, A. V.; Yushkov, G. Yu.

    2008-02-15

    A high current, multi charged, metal ion source using electron heating of vacuum arc plasma by high power gyrotron radiation has been developed. The plasma is confined in a simple mirror trap with peak magnetic field in the plug up to 2.5 T, mirror ratio of 3-5, and length variable from 15 to 20 cm. Plasma formed by a cathodic vacuum arc is injected into the trap either (i) axially using a compact vacuum arc plasma gun located on axis outside the mirror trap region or (ii) radially using four plasma guns surrounding the trap at midplane. Microwave heating of the mirror-confined, vacuum arc plasma is accomplished by gyrotron microwave radiation of frequency 75 GHz, power up to 200 kW, and pulse duration up to 150 {mu}s, leading to additional stripping of metal ions by electron impact. Pulsed beams of platinum ions with charge state up to 10+, a mean charge state over 6+, and total (all charge states) beam current of a few hundred milliamperes have been formed.

  3. Columbia University flow instability experimental program: Volume 2. Single tube uniformly heated tests -- Part 2: Uncertainty analysis and data

    SciTech Connect (OSTI)

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

    1990-05-01

    In June 1988, Savannah River Laboratory requested that the Heat Transfer Research Facility modify the flow excursion program, which had been in progress since November 1987, to include testing of single tubes in vertical down-flow over a range of length to diameter (L/D) ratios of 100 to 500. The impetus for the request was the desire to obtain experimental data as quickly as possible for code development work. In July 1988, HTRF submitted a proposal to SRL indicating that by modifying a facility already under construction the data could be obtained within three to four months. In January 1990, HTFR issued report CU-HTRF-T4, part 1. This report contained the technical discussion of the results from the single tube uniformly heated tests. The present report is part 2 of CU-HTRF-T4 which contains further discussion of the uncertainty analysis and the complete set of data.

  4. Gravitational collapse of a spherical star with heat flow as a possible energy mechanism of gamma-ray bursts

    E-Print Network [OSTI]

    Zhe Chang; Cheng-Bo Guan; Chao-Guang Huang; Xin Li

    2008-03-26

    We investigate the gravitational collapse of a spherically symmetric, inhomogeneous star, which is described by a perfect fluid with heat flow and satisfies the equation of state $p=\\rho/3$ at its center. In the process of the gravitational collapsing, the energy of the whole star is emitted into space. And the remaining spacetime is a Minkowski one without a remnant at the end of the process. For a star with a solar mass and solar radius, the total energy emitted is at the order of $10^{54}$ {\\rm erg}, and the time-scale of the process is about $8s$. These are in the typical values for a gamma-ray burst. Thus, we suggest the gravitational collapse of a spherical star with heat flow as a possible energy mechanism of gamma-ray bursts.

  5. High Performance Computing linear algorithms for two-phase flow in porous media

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    High Performance Computing linear algorithms for two-phase flow in porous media Robert Eymard High Performance Computing techniques. This implies to handle the difficult problem of solving

  6. New Whole-House Solutions Case Study: Testing Ductless Heat Pumps in High-Performance Affordable Housing, the Woods at Golden Given - Tacoma, Washington

    SciTech Connect (OSTI)

    2015-06-01

    The Woods is a 30-home, high- performance, energy efficient sustainable community built by Habitat for Humanity (HFH). With Support from Tacoma Public Utilities, Washington State University (part of the Building America Partnership for Improved Residential Construction) is researching the energy performance of these homes and the ductless heat pumps (DHP) they employ. This project provides Building America with an opportunity to: field test HVAC equipment, ventilation system air flows, building envelope tightness, lighting, appliance, and other input data that are required for preliminary Building Energy Optimization (BEopt™) modeling and ENERGY STAR® field verification; analyze cost data from HFH and other sources related to building-efficiency measures that focus on the DHP/hybrid heating system and heat recovery ventilation system; evaluate the thermal performance and cost benefit of DHP/hybrid heating systems in these homes from the perspective of homeowners; compare the space heating energy consumption of a DHP/electric resistance (ER) hybrid heating system to that of a traditional zonal ER heating system; conduct weekly "flip-flop tests" to compare space heating, temperature, and relative humidity in ER zonal heating mode to DHP/ER mode.

  7. Multi-Scale Experiments in Turbulent Subcooled Boiling Flow Through a Square Channel with a Single Heated Wall 

    E-Print Network [OSTI]

    Estrada Perez, Carlos Eduardo

    2014-12-12

    flow through a square channel. The explored visualization techniques were: 1) Particle tracking velocimetry (PTV), which provides velocity measurements of the liquid phase, 2) High-speed shadowgraphy (HSS) which is used to study the dispersed phase...

  8. High throughput analysis of samples in flowing liquid

    DOE Patents [OSTI]

    Ambrose, W. Patrick (Los Alamos, NM); Grace, W. Kevin (Los Alamos, NM); Goodwin, Peter M. (Los Alamos, NM); Jett, James H. (Los Alamos, NM); Orden, Alan Van (Fort Collins, CO); Keller, Richard A. (White Rock, NM)

    2001-01-01

    Apparatus and method enable imaging multiple fluorescent sample particles in a single flow channel. A flow channel defines a flow direction for samples in a flow stream and has a viewing plane perpendicular to the flow direction. A laser beam is formed as a ribbon having a width effective to cover the viewing plane. Imaging optics are arranged to view the viewing plane to form an image of the fluorescent sample particles in the flow stream, and a camera records the image formed by the imaging optics.

  9. Parametric Analyses of Heat Removal from High Level Waste Tanks

    SciTech Connect (OSTI)

    TRUITT, J.B.

    2000-06-05

    The general thermal hydraulics program GOTH-SNF was used to predict the thermal response of the waste in tanks 241-AY-102 and 241-AZ-102 when mixed by two 300 horsepower mixer pumps. This mixing was defined in terms of a specific waste retrieval scenario. Both dome and annulus ventilation system flow are necessary to maintain the waste within temperature control limits during the mixing operation and later during the sludge-settling portion of the scenario are defined.

  10. CONNECTING STAR FORMATION QUENCHING WITH GALAXY STRUCTURE AND SUPERMASSIVE BLACK HOLES THROUGH GRAVITATIONAL HEATING OF COOLING FLOWS

    SciTech Connect (OSTI)

    Guo, Fulai

    2014-12-20

    Recent observations suggested that star formation quenching in galaxies is related to galaxy structure. Here we propose a new mechanism to explain the physical origin of this correlation. We assume that while quenching is maintained in quiescent galaxies by a feedback mechanism, cooling flows in the hot halo gas can still develop intermittently. We study cooling flows in a large suite of around 90 hydrodynamic simulations of an isolated galaxy group, and find that the flow development depends significantly on the gravitational potential well in the central galaxy. If the galaxy's gravity is not strong enough, cooling flows result in a central cooling catastrophe, supplying cold gas and feeding star formation to galactic bulges. When the bulge grows prominent enough, compressional heating starts to offset radiative cooling and maintains cooling flows in a long-term hot mode without producing a cooling catastrophe. Our model thus describes a self-limited growth channel for galaxy bulges and naturally explains the connection between quenching and bulge prominence. In particular, we explicitly demonstrate that M{sub ?}/R{sub eff}{sup 1.5} is a good structural predictor of quenching. We further find that the gravity from the central supermassive black hole also affects the bimodal fate of cooling flows, and we predict a more general quenching predictor to be M{sub bh}{sup 1.6}M{sub ?}/R{sub eff}{sup 1.5}, which may be tested in future observational studies.

  11. A Stable Vanadium Redox-Flow Battery with High Energy Density for Large-scale Energy Storage

    SciTech Connect (OSTI)

    Li, Liyu; Kim, Soowhan; Wang, Wei; Vijayakumar, M.; Nie, Zimin; Chen, Baowei; Zhang, Jianlu; Xia, Guanguang; Hu, Jian Z.; Graff, Gordon L.; Liu, Jun; Yang, Zhenguo

    2011-05-01

    Low cost, high performance redox flow batteries are highly demanded for up to multi-megawatt levels of renewable and grid energy storage. Here, we report a new vanadium redox flow battery with a significant improvement over the current technologies. This new battery utilizes a sulfate-chloride mixed solution, which is capable of dissolving more than 2.5 M vanadium or about a 70% increase in the energy storage capacity over the current vanadium sulfate system. More importantly, the new electrolyte remains stable over a wide temperature range of -5 to 60oC, potentially eliminating the need of active heat management. Its high energy density, broad operational temperature window, and excellent electrochemical performance would lead to a significant reduction in the cost of energy storage, thus accelerating its market penetration.

  12. High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    SciTech Connect (OSTI)

    Tarau, Calin; Walker, Kara L.; Anderson, William G.

    2009-03-16

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling converter provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling engine. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 deg. C while the heat losses caused by the addition of the VCHP are 1.8 W.

  13. Anomalous specific heat in high-density QED and QCD

    E-Print Network [OSTI]

    A. Ipp; A. Gerhold; A. Rebhan

    2003-09-22

    Long-range quasi-static gauge-boson interactions lead to anomalous (non-Fermi-liquid) behavior of the specific heat in the low-temperature limit of an electron or quark gas with a leading $T\\ln T^{-1}$ term. We obtain perturbative results beyond the leading log approximation and find that dynamical screening gives rise to a low-temperature series involving also anomalous fractional powers $T^{(3+2n)/3}$. We determine their coefficients in perturbation theory up to and including order $T^{7/3}$ and compare with exact numerical results obtained in the large-$N_f$ limit of QED and QCD.

  14. High Fidelity Simulation of Complex Suspension Flow for Practical...

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

    A visualization of the flow of concrete, a complex suspension A visualization of the flow of concrete, a complex suspension. In this snapshot of the simulation, the stress on each...

  15. Water and Solute Flow in a Highly-Structured Soil 

    E-Print Network [OSTI]

    Hallmark, C. Tom; Wilding, Larry P.; McInnes, Kevin J.; Heuvelman, Willem J.

    1993-01-01

    to groundwater may be related to the degree of flow path channelization (convergence or divergence of water flow paths). This project was designed to test the feasibility of measuring the degree of channelization as water percolates through structured soils. A...

  16. Ice flow sensitivity to geothermal heat flux of Pine Island Glacier, Antarctica

    E-Print Network [OSTI]

    Larour, E; Morlighem, M; Seroussi, H; Schiermeier, J; Rignot, E; Rignot, E

    2012-01-01

    as heat available from geothermal energy. The consequence isbasal friction and geothermal energy are all on the sameis influenced by geothermal energy in the slow moving areas

  17. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    type air-source VRF system and a GSHP system that uses single-stage scroll compressors and vertical ground loop heat exchanger (

  18. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    dual compressor available on the market Compared with the selected building, a more energy efficient building will have lower space cooling and heating

  19. Heat treated 9 Cr-1 Mo steel material for high temperature application

    DOE Patents [OSTI]

    Jablonski, Paul D.; Alman, David; Dogan, Omer; Holcomb, Gordon; Cowen, Christopher

    2012-08-21

    The invention relates to a composition and heat treatment for a high-temperature, titanium alloyed, 9 Cr-1 Mo steel exhibiting improved creep strength and oxidation resistance at service temperatures up to 650.degree. C. The novel combination of composition and heat treatment produces a heat treated material containing both large primary titanium carbides and small secondary titanium carbides. The primary titanium carbides contribute to creep strength while the secondary titanium carbides act to maintain a higher level of chromium in the finished steel for increased oxidation resistance, and strengthen the steel by impeding the movement of dislocations through the crystal structure. The heat treated material provides improved performance at comparable cost to commonly used high-temperature steels such as ASTM P91 and ASTM P92, and requires heat treatment consisting solely of austenization, rapid cooling, tempering, and final cooling, avoiding the need for any hot-working in the austenite temperature range.

  20. High energy bursts from a solid state laser operated in the heat capacity limited regime

    DOE Patents [OSTI]

    Albrecht, Georg (Livermore, CA); George, E. Victor (Livermore, CA); Krupke, William F. (Pleasanton, CA); Sooy, Walter (Pleasanton, CA); Sutton, Steven B. (Manteca, CA)

    1996-01-01

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes.

  1. High energy bursts from a solid state laser operated in the heat capacity limited regime

    DOE Patents [OSTI]

    Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

    1996-06-11

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

  2. Development and Analysis of Advanced High-Temperature Technology for Nuclear Heat Transport and Power Conversion

    SciTech Connect (OSTI)

    Per F. Peterson

    2010-03-01

    This project by the Thermal Hydraulics Research Laboratory at U.C. Berkeley Studied advanced high-temperature heat transport and power conversion technology, in support of the Nuclear Hydrogen Initiative and Generation IV.

  3. High Efficiency Microturbine with Integral Heat Recovery- Presentation by Capstone Turbine Corporation, June 2011

    Broader source: Energy.gov [DOE]

    Presentation on High Efficiency Microturbine with Integral Heat Recovery, given by John Nourse of Capstone Turbine Corporation, at the U.S. DOE Industrial Distributed Energy Portfolio Review Meeting in Washington, D.C. on June 1-2, 2011.

  4. High-Performance Thermoelectric Devices Based on Abundant Silicide Materials for Vehicle Waste Heat Recovery

    Office of Energy Efficiency and Renewable Energy (EERE)

    Development of high-performance thermoelectric devices for vehicle waste heat recovery will include fundamental research to use abundant promising low-cost thermoelectric materials, thermal management and interfaces design, and metrology

  5. Hanford waste treatment plant Immobilized High Level Waste (IHLW) canister radiation dose rate and radiolytic heat load analysis

    SciTech Connect (OSTI)

    PIERSON, R.M.

    2003-09-02

    This document provides an analysis of anticipated radiation dose rates and heat loads for immobilized high level waste (IHW) canisters

  6. 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

  7. Water-heating dehumidifier

    DOE Patents [OSTI]

    Tomlinson, John J. (Knoxville, TN)

    2006-04-18

    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.

  8. Project Profile: High Operating Temperature Liquid Metal Heat...

    Office of Environmental Management (EM)

    multi-target co-sputtering system to create massive compositional libraries in thin-film forms and employ high-throughput characterization methods to rapidly screen candidate...

  9. HEATS OF COMBUSTION OF HIGH TEMPERATURE POLYMERS Richard N. Walters*, Stacey M. Hackett* and Richard E. Lyon

    E-Print Network [OSTI]

    Laughlin, Robert B.

    1 HEATS OF COMBUSTION OF HIGH TEMPERATURE POLYMERS Richard N. Walters*, Stacey M. Hackett Creek Avenue, Building C Egg Harbor Township, New Jersey 08234 ABSTRACT The heats of combustion to thermochemical calculations of the net heat of combustion from oxygen consumption and the gross heat

  10. High exhaust temperature, zoned, electrically-heated particulate matter filter

    SciTech Connect (OSTI)

    Gonze, Eugene V.; Paratore, Jr., Michael J.; Bhatia, Garima

    2015-09-22

    A system includes a particulate matter (PM) filter, an electric heater, and a control circuit. The electric heater includes multiple zones, which each correspond to longitudinal zones along a length of the PM filter. A first zone includes multiple discontinuous sub-zones. The control circuit determines whether regeneration is needed based on an estimated level of loading of the PM filter and an exhaust flow rate. In response to a determination that regeneration is needed, the control circuit: controls an operating parameter of an engine to increase an exhaust temperature to a first temperature during a first period; after the first period, activates the first zone; deactivates the first zone in response to a minimum filter face temperature being reached; subsequent to deactivating the first zone, activates a second zone; and deactivates the second zone in response to the minimum filter face temperature being reached.

  11. Precision control of high temperature furnaces using an auxiliary power supply and charged practice current flow

    DOE Patents [OSTI]

    Pollock, George G. (San Ramon, CA)

    1997-01-01

    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved.

  12. Precision control of high temperature furnaces using an auxiliary power supply and charged particle current flow

    DOE Patents [OSTI]

    Pollock, G.G.

    1997-01-28

    Two power supplies are combined to control a furnace. A main power supply heats the furnace in the traditional manner, while the power from the auxiliary supply is introduced as a current flow through charged particles existing due to ionized gas or thermionic emission. The main power supply provides the bulk heating power and the auxiliary supply provides a precise and fast power source such that the precision of the total power delivered to the furnace is improved. 5 figs.

  13. Energy Efficiency Supporting Policy and Heat Pumping Technology in Japan

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    conservation 4 Feature ( Newly developed) Design for CO2 refrigerant Compressor for high pressure Counter flow Heat exchanger Over 15 manufactures have taken part in the markets ever since. Owing to newly developed feature Counter flow Heat exchanger Heat pump unit Storage tank Ref: TEPCO Website Ref: HPTCJ HP Space

  14. Particle image velocimetry measurements for opposing flow in a vertical channel with a differential and asymmetric heating condition

    SciTech Connect (OSTI)

    Martinez-Suastegui, L. [Graduate Student, Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, C.U., Mexico 04510 D.F. (Mexico); Trevino, C. [Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, C.U., Mexico 04510 D.F. (Mexico)

    2007-10-15

    Particle image velocimetry (PIV) measurements were carried out in an experimental investigation of laminar mixed convection in a vertical duct with a square cross-section. The main downward water-flow is driven by gravity while a portion of a lateral side is heated, and buoyancy forces produce non-stationary vortex structures close to the heated region. Various ranges of the Grashof number, Gr are studied in combination with the Reynolds number, Re varying from 300 to 700. The values of the generalized buoyancy parameter or Richardson number, Ri = Gr/Re{sup 2} parallel to the Grashof number are included in the results. The influence of these nondimensional parameters and how they affect the fluid flow structure and vortex sizes and locations are reported. The flow patterns are nonsymmetric, periodic, and exhibit increasing complexity and frequency for increasing buoyancy. For the averaged values of the resulting vortex dimensions, it was found that a better and more congruent representation occurs when employing the Grashof and Reynolds numbers as independent parameters. (author)

  15. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

  16. High strength and heat resistant chromium steels for sodium-cooled fast reactors.

    SciTech Connect (OSTI)

    Kamal, S.; Grandy, C.; Farmer, M.; Brunsvold, A.

    2004-12-22

    This report provides the results of a preliminary phase of a project supporting the Advanced Nuclear Fuel Cycle Technology Initiative at ANL. The project targets the Generation IV nuclear energy systems, particularly the area of reducing the cost of sodium-cooled fast-reactors by utilizing innovative materials. The main goal of the project is to provide the nuclear heat exchanger designers a simplified means to quantify the cost advantages of the recently developed high strength and heat resistant ferritic steels with 9 to 13% chromium content. The emphasis in the preliminary phase is on two steels that show distinctive advantages and have been proposed as candidate materials for heat exchangers and also for reactor vessels and near-core components of Gen IV reactors. These steels are the 12Cr-2W (HCM12A) and 9Cr-1MoVNb (modified 9Cr-1Mo). When these steels are in tube form, they are referred to in ASTM Standards as T122 and T91, respectively. A simple thermal-hydraulics analytical model of a counter-flow, shell-and-tube, once-through type superheated steam generator is developed to determine the required tube length and tube wall temperature profile. The single-tube model calculations are then extended to cover the following design criteria: (i) ratio of the tube stress due to water/steam pressure to the ASME B&PV Code allowable stress, (ii) ratio of the strain due to through-tube-wall temperature differences to the material fatigue limit, (iii) overall differential thermal expansion between the tube and shell, and (iv) total amount of tube material required for the specified heat exchanger thermal power. Calculations were done for a 292 MW steam generator design with 2200 tubes and a steam exit condition of 457 C and 16 MPa. The calculations were performed with the tubes made of the two advanced ferritic steels, 12Cr-2W and 9Cr-1MoVNb, and of the most commonly used steel, 2 1/4Cr-1Mo. Compared to the 2 1/4Cr-1Mo results, the 12Cr-2W tubes required 29% less material and the 9Cr-1MoVNb tubes required 25% less material. Also, with the advanced steels, the thermal strains in the tubes and differential thermal expansion between tubes and shell were significantly better. For steam generators with higher steam exit temperatures, the benefits of the advanced steels become much larger. A thorough search for the thermal and mechanical properties of the two advanced steels was conducted. A summary of the search results is provided. It shows what is presently known about these two advanced steels and what still needs to be determined so that they can be used in nuclear heat exchanger designs. Possible follow up steps are outlined.

  17. Momentum and heat fluxes in a turbulent air flow over a wet, smooth boundary 

    E-Print Network [OSTI]

    Rice, Warren

    1958-01-01

    groundwater-land surface model, ParFlow.CLM, to develop a spatial distributed ecohydrological model at the stand scale (~1000 m^(2)). The modified ParFlow.CLM was used to conduct a 8-year simulation with half hourly time step at a AmeriFlux oak savanna site...

  18. Electrical heating of soils using high efficiency electrode patterns and power phases

    DOE Patents [OSTI]

    Buettner, Harley M. (Livermore, CA)

    1999-01-01

    Powerline-frequency electrical (joule) heating of soils using a high efficiency electrode configuration and power phase arrangement. The electrode configuration consists of several heating or current injection electrodes around the periphery of a volume of soil to be heated, all electrodes being connected to one phase of a multi-phase or a single-phase power system, and a return or extraction electrode or electrodes located inside the volume to be heated being connected to the remaining phases of the multi-phase power system or to the neutral side of the single-phase power source. This electrode configuration and power phase arrangement can be utilized anywhere where powerline frequency soil heating is applicable and thus has many potential uses including removal of volatile organic compounds such as gasoline and tricholorethylene (TCE) from contaminated areas.

  19. 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 ...

  20. Heat transfer characteristics of circular impinging jet arrays in an annular section with cross flow effects 

    E-Print Network [OSTI]

    Mhetras, Shantanu Prakash

    2002-01-01

    Jet impingement has been shown to be an effective method for enhancing convective heat transfer. There are a variety of applications of impinging jets in industry, including tempering and shaping of glass, annealing of metal and plastic sheets...

  1. In-Situ Thermal Conductivity Testing Using a Portable Heat Flow Meter 

    E-Print Network [OSTI]

    Harr, K. S.; Hutto, F. B., Jr.

    1979-01-01

    A method has been developed for measuring heat losses from insulated systems in the field. While the measurements are not as precise as those made under laboratory conditions, they are more indicative of actual in service conditions. Extensive field...

  2. Liquid-vapour phase change and multiphase flow heat transfer in single micro-channels using pure liquids and nano-fluids 

    E-Print Network [OSTI]

    Wang, Yuan

    2011-11-22

    Heat management in high thermal-density systems such as CPU chips, nuclear reactors and compact heat exchangers is confronting rising challenges due to ever more miniaturized and intensified processes. While searching ...

  3. Waste Heat Recovery from High Temperature Off-Gases from Electric Arc Furnace

    SciTech Connect (OSTI)

    Nimbalkar, Sachin U [ORNL; Thekdi, Arvind [E3M Inc; Keiser, James R [ORNL; Storey, John Morse [ORNL

    2014-01-01

    This article presents a study and review of available waste heat in high temperature Electric Arc Furnace (EAF) off gases and heat recovery techniques/methods from these gases. It gives details of the quality and quantity of the sensible and chemical waste heat in typical EAF off gases, energy savings potential by recovering part of this heat, a comprehensive review of currently used waste heat recovery methods and potential for use of advanced designs to achieve a much higher level of heat recovery including scrap preheating, steam production and electric power generation. Based on our preliminary analysis, currently, for all electric arc furnaces used in the US steel industry, the energy savings potential is equivalent to approximately 31 trillion Btu per year or 32.7 peta Joules per year (approximately $182 million US dollars/year). This article describes the EAF off-gas enthalpy model developed at Oak Ridge National Laboratory (ORNL) to calculate available and recoverable heat energy for a given stream of exhaust gases coming out of one or multiple EAF furnaces. This Excel based model calculates sensible and chemical enthalpy of the EAF off-gases during tap to tap time accounting for variation in quantity and quality of off gases. The model can be used to estimate energy saved through scrap preheating and other possible uses such as steam generation and electric power generation using off gas waste heat. This article includes a review of the historical development of existing waste heat recovery methods, their operations, and advantages/limitations of these methods. This paper also describes a program to develop and test advanced concepts for scrap preheating, steam production and electricity generation through use of waste heat recovery from the chemical and sensible heat contained in the EAF off gases with addition of minimum amount of dilution or cooling air upstream of pollution control equipment such as bag houses.

  4. Vitiated ethane oxidation in a high-pressure flow reactor

    SciTech Connect (OSTI)

    Walters, K.M.; Bowman, C.T.

    2009-10-15

    Vitiated combustion processes offer the potential to improve the thermodynamic efficiency in hydrocarbon-fueled combustion systems, providing a subsequent decrease in energy-specific CO{sub 2} emissions along with a decrease in the emission levels of nitrogen oxides (NO{sub x}) and particulate matter. The present work comprises an experimental and modeling study of vitiated ethane oxidation in a high-pressure flow reactor, with pressures of 1-6 bar, O{sub 2} mole fractions of 3.5-7.0%, temperatures of 1075-1100 K and 15-18 mole.% H{sub 2}O. Time-history measurements of species are used to characterize the overall rate of reaction and track the fuel-carbon through intermediate and product species. A one-dimensional mixing-reacting model that accounts for partial oxidation during reactant mixing is used in conjunction with a detailed kinetic mechanism. Changes in competing pathways due to variations in pressure and O{sub 2} mole fraction give rise to the complex pressure dependence seen in the experiments. (author)

  5. Low Magnetic Reynolds Number Hypersonic MHD Flow Using High Order WENO Schemes

    E-Print Network [OSTI]

    Zha, Gecheng

    diffusion scheme for 3D Navier-Stokes equa- tions. We present results for hypersonic laminar flows around diffusion E-CUSP (LDE) scheme with a fifth order WENO scheme was developed to resolve flow fields with shockLow Magnetic Reynolds Number Hypersonic MHD Flow Using High Order WENO Schemes Jaejin Lee , Manuel

  6. Temperature and Material Flow Prediction in Friction-Stir Spot Welding of Advanced High-Strength Steel

    SciTech Connect (OSTI)

    Miles, Michael; Karki, U.; Hovanski, Yuri

    2014-10-01

    Friction-stir spot welding (FSSW) has been shown to be capable of joining advanced high-strength steel, with its flexibility in controlling the heat of welding and the resulting microstructure of the joint. This makes FSSW a potential alternative to resistance spot welding if tool life is sufficiently high, and if machine spindle loads are sufficiently low that the process can be implemented on an industrial robot. Robots for spot welding can typically sustain vertical loads of about 8 kN, but FSSW at tool speeds of less than 3000 rpm cause loads that are too high, in the range of 11–14 kN. Therefore, in the current work, tool speeds of 5000 rpm were employed to generate heat more quickly and to reduce welding loads to acceptable levels. Si3N4 tools were used for the welding experiments on 1.2-mm DP 980 steel. The FSSW process was modeled with a finite element approach using the Forge* software. An updated Lagrangian scheme with explicit time integration was employed to predict the flow of the sheet material, subjected to boundary conditions of a rotating tool and a fixed backing plate. Material flow was calculated from a velocity field that is two-dimensional, but heat generated by friction was computed by a novel approach, where the rotational velocity component imparted to the sheet by the tool surface was included in the thermal boundary conditions. An isotropic, viscoplastic Norton-Hoff law was used to compute the material flow stress as a function of strain, strain rate, and temperature. The model predicted welding temperatures to within percent, and the position of the joint interface to within 10 percent, of the experimental results.

  7. Modelling for post-dryout heat transfer and droplet sizes at low pressure and low flow conditions

    SciTech Connect (OSTI)

    Jeong, H.Y.; No, H.C. [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Nuclear Engineering] [Korea Advanced Inst. of Science and Technology, Taejon (Korea, Republic of). Dept. of Nuclear Engineering

    1996-10-01

    A correlation describing the initial droplet size just after the CHF position at low mass flux is suggested through regression analysis. The history-dependent post-dryout model of Varone and Rohsenow replaced by the Webb-Chen model for wall-vapor heat transfer is used as a reference model in the analysis. In the post-dryout region at low pressure and low flow, it is found that the suggested one-dimensional mechanistic model is valid only in the churn-turbulent flow regime (j*{sub g} = 0.5 {approximately} 4.5). It is also suggested that the droplet size generated from the churn-turbulent surface is dependent not only on the pressure but also on the vapor velocity. It turns out that the present model can predict the measured cladding and vapor temperatures within 20% and 15%, respectively.

  8. Development of a High Performance Air Source Heat Pump for the US Market

    SciTech Connect (OSTI)

    Abdelaziz, Omar [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL; Gao, Zhiming [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Iu, Ipseng [ORNL] [ORNL

    2011-01-01

    Heat pumps present a significant advantage over conventional residential heating technologies due to higher energy efficiencies and less dependence on imported oil. The US development of heat pumps dates back to the 1930 s with pilot units being commercially available in the 1950 s. Reliable and cost competitive units were available in the US market by the 1960 s. The 1973 oil embargo led to increased interest in heat pumps prompting significant research to improve performance, particularly for cold climate locations. Recent increasing concerns on building energy efficiency and environmental emissions have prompted a new wave of research in heat pump technology with special emphasis on reducing performance degradation at colder outdoor air temperatures. A summary of the advantages and limitations of several performance improvement options sought for the development of high performance air source heat pump systems for cold climate applications is the primary focus of this paper. Some recommendations for a high performance cold climate heat pump system design most suitable for the US market are presented.

  9. High Operating Temperature Liquid Metal Heat Transfer Fluids (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-12-01

    The University of California, Los Angeles, the University of California, Berkeley, and Yale University is one of the 2012 SunShot CSP R&D awardees for their Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids. This fact sheet explains the motivation, description, and impact of the project.

  10. High-Harmonic Fast-Wave Power Flow Along Magnetic Field Lines in the Scrape-Off Layer of NSTX

    SciTech Connect (OSTI)

    Perkins, R. J. [Princeton Plasma Physics Laboratory (PPPL); Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Kramer, G. [Princeton Plasma Physics Laboratory (PPPL); Ahn, Joonwook [ORNL; Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); Diallo, A. [Princeton Plasma Physics Laboratory (PPPL); Gerhardt, S. [Princeton Plasma Physics Laboratory (PPPL); Gray, T. K. [Oak Ridge National Laboratory (ORNL); Green, David L [ORNL; Jaeger, Erwin Frederick [ORNL; Jaworski, M. A. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); McLean, Adam G [ORNL; Maingi, Rajesh [ORNL; Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Roquemore, L. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Sabbagh, S. A. [Columbia University; Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)

    2012-01-01

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast-wave heating and current drive.

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

    SciTech Connect (OSTI)

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

    1980-09-01

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

  12. Can High Frequency Acoustic Waves Heat the Quiet Sun Chromosphere?

    E-Print Network [OSTI]

    Mats Carlsson; Viggo H. Hansteen; Bart De Pontieu; Scott McIntosh; Theodore D. Tarbell; Dick Shine; Saku Tsuneta; Yukio Katsukawa; Kiyoshi Ichimoto; Yoshinori Suematsu; Toshifumi Shimizu; Shin'ichi Nagata

    2007-09-21

    We use Hinode/SOT Ca II H-line and blue continuum broadband observations to study the presence and power of high frequency acoustic waves at high spatial resolution. We find that there is no dominant power at small spatial scales; the integrated power using the full resolution of Hinode (0.05'' pixels, 0.16'' resolution) is larger than the power in the data degraded to 0.5'' pixels (TRACE pixel size) by only a factor of 1.2. At 20 mHz the ratio is 1.6. Combining this result with the estimates of the acoustic flux based on TRACE data of Fossum & Carlsson (2006), we conclude that the total energy flux in acoustic waves of frequency 5-40 mHz entering the internetwork chromosphere of the quiet Sun is less than 800 W m$^{-2}$, inadequate to balance the radiative losses in a static chromosphere by a factor of five.

  13. Large-Eddy Simulation of Flow and Pollutant Transport in Urban Street Canyons with Ground Heating

    E-Print Network [OSTI]

    Li, Xian-Xiang

    Our study employed large-eddy simulation (LES) based on a one-equation subgrid-scale model to investigate the flow field and pollutant dispersion characteristics inside urban street canyons. Unstable thermal stratification ...

  14. Modeling Free Convection Flow of Liquid Hydrogen within a Cylindrical Heat Exchanger Cooled to 14 K

    E-Print Network [OSTI]

    Yang, S.W.; Oxford U.

    2004-01-01

    M. A. , “Comments on Liquid Hydrogen Absorbers for MICE,”Gas at 14 to 18 K and Liquid Hydrogen at 20 K circulated byFREE CONVECTION FLOW OF LIQUID HYDROGEN WITHIN A CYLINDRICAL

  15. High-Efficiency Commercial Cold Climate Heat Pump

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡HighApproachesDepartment

  16. High-Performance Refrigerator Using Novel Rotating Heat Exchanger |

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartmentHigh-EfficiencyPatrick HughesbyDepartment

  17. Voltage breakdown limits at a high material temperature for rapid pulse heating in a vacuum

    SciTech Connect (OSTI)

    Pincosy, P A; Speer, R

    1999-06-07

    The proposed Advanced Hydro Facility (AHF) is required to produce multi-pulse radiographs. Electron beam pulse machines with sub-microsecond repetition are not yet available to test the problem of electron beam propagation through the hydro-dynamically expanding plasma from the nearby previously heated target material. A proposed test scenario includes an ohmically heated small volume of target material simulating the electron beam heating, along with an actual electron beam pulse impinging on nearby target material. A pulse power heating circuit was tested to evaluate the limits of pulse heating a small volume of material to tens of kilo-joules per gram. The main pulse heating time (50 to 100 ns) was to simulate the electron beam heating of a converter target material. To avoid skin heating non-uniformity a longer time scale pulse of a few microseconds first heats the target material to a few thousand degrees near the liquid to vapor transition. Under this state the maximum electric field that the current carrying conductor can support is the important parameter for insuring that the 100 ns heating pulse can deposit sufficient power. A small pulse power system was built for tests of this limit. Under cold conditions the vacuum electric field hold-off limit has been quoted as high as many tens of kilovolts per centimeter. The tests for these experiments found that the vacuum electric field hold-off was limited to a few kilovolts per centimeter when the material approached melting temperatures. Therefore the proposed test scenario for AHF was not achievable.*

  18. High Efficiency Microturbine with Integral Heat Recovery | Department of

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh EfficiencyEnergy

  19. 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 Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHighJian Li,1 DOEFuel

  20. High-Efficiency Commercial Cold Climate Heat Pump

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡HighApproachesDepartment ofEngines

  1. Sensitivity studies of heat transfer: forced convection across a cylindrical pipe and duct flow

    E-Print Network [OSTI]

    Ferrantelli, Andrea; Viljanen, Martti

    2013-01-01

    We consider two common heat transfer processes and perform a through sensitivity study of the variables involved. We derive and discuss analytical formulas for the heat transfer coefficient in function of film velocity, air temperature and pipe diameter. The according plots relate to a qualitative analysis of the multi-variable function $h$, according to functional optimization. For each process, we provide with graphs and tables of the parameters of interest, such as the Reynolds number. This method of study and the specific values can constitute a useful reference for didactic purposes.

  2. Plasma flow at a high Mach-number

    SciTech Connect (OSTI)

    Yu, Bing; Hameiri, Eliezer

    2013-09-15

    Unlike the case of static magnetohydrodynamic (MHD) equilibria, where an expansion in large aspect ratio of toroidal devices is common, cases of MHD equilibria with flow are rarely treated this way, and when this is done the expansion tends to be only partial. The main reason for the difference seems to be the difficulty of expanding the larger system of equilibrium equations with flow. Here, we use a recent expansion technique which employs a variational principle to simplify the process [E. Hameiri, Phys. Plasmas 20, 024504 (2013)]. We treat four cases of MHD equilibria with flow, developing their asymptotic expansions in full, and for an application consider the effect of the flow on the Shafranov shift.

  3. STOCHASTIC HEATING, DIFFERENTIAL FLOW, AND THE ALPHA-TO-PROTON TEMPERATURE RATIO IN THE SOLAR WIND

    SciTech Connect (OSTI)

    Chandran, B. D. G.; Verscharen, D.; Isenberg, P. A.; Bourouaine, S.; Quataert, E.; Kasper, J. C. E-mail: s.bourouaine@unh.edu E-mail: daniel.verscharen@unh.edu E-mail: jkasper@cfa.harvard.edu

    2013-10-10

    We extend previous theories of stochastic ion heating to account for the motion of ions along the magnetic field B . We derive an analytic expression for the temperature ratio T{sub i}/T{sub p} in the solar wind assuming that stochastic heating is the dominant ion heating mechanism, where T{sub i} is the perpendicular temperature of species i and T{sub p} is the perpendicular proton temperature. This expression describes how T{sub i}/T{sub p} depends upon U{sub i} and ?{sub ?p}, where U{sub i} is the average velocity along B of species i in the proton frame and ?{sub ?p} is the ratio of the parallel proton pressure to the magnetic pressure, which we take to be ?< 1. We compare our model with previously published measurements of alpha particles and protons from the Wind spacecraft. We find that stochastic heating offers a promising explanation for the dependence of T{sub ?}/T{sub p} on U{sub ?} and ?{sub ?p} when the fractional cross helicity and Alfvén ratio at the proton-gyroradius scale have values that are broadly consistent with solar-wind measurements. We also predict how the temperatures of other ion species depend on their drift speeds.

  4. Experimental investigation on heat transfer for two-phase flow under natural convection

    SciTech Connect (OSTI)

    Amizic, Milan; Guyez, Estelle; Seiler, Jean-Marie

    2012-07-01

    In the frame of severe accident research for the second and the third generation of nuclear power plants, some aspects of the concrete cavity ablation during the molten corium - concrete interaction are still remaining issues. The determination of heat transfer along the interfacial region between the molten corium pool and the ablating basemat concrete is crucial for the assessment of concrete ablation progression and eventually the basemat melt-through. For the purpose of experimental investigation of thermal-hydraulics inside a liquid pool agitated by gas bubbles, the CLARA project has been launched jointly by CEA, EDF, IRSN, GDF-Suez and SARNET. The CLARA experiments are performed using simulant materials and they reveal the influence of superficial gas velocity, liquid viscosity and pool geometry on the heat transfer coefficient between the internally heated liquid pool and vertical and horizontal pool walls maintained at uniform temperature. The first test campaign has been conducted with the smallest pool configuration (50 cm x 25 cm x 25 cm). The tests have been performed with liquids covering a wide range of dynamic viscosity from approximately 1 mPa s to 10000 mPa s. This paper presents some preliminary conclusions deduced from the experiments which involve a liquid pool with the gas injection only from the bottom plate. A comparison with existing models for the assessment of heat transfer has also been carried out. (authors)

  5. Application of a two-fluid model to simulate the heating of two-phase flows.

    E-Print Network [OSTI]

    Saleh, Khaled

    using an analytical solution. Eventually, a test case of the heating of a mixture of steam and water is presented, which is representative of a steam generator device. 1 Introduction Most of the industrial either as a coolant fluid or to ensure the production of mechanical work through the turbines which

  6. Simulation of three-dimensional laminar flow and heat transfer in an array of parallel microchannels 

    E-Print Network [OSTI]

    Mlcak, Justin Dale

    2009-05-15

    ranges from 50 to 400. A constant heat flux of 90 W/cm2 is applied to the northern face of the computational domain, which simulates thermal energy generation from an integrated circuit. A simplified model is validated against analytical fully developed...

  7. Study of Laminar Flow Forced Convection Heat Transfer Behavior of a Phase Change Material Fluid 

    E-Print Network [OSTI]

    Ravi, Gurunarayana

    2010-01-14

    takes into account the melting point and latent heat of fusion of the PCM as shown in Eq. (14) and (15). () ( ) ( ) b sl m p m f 1 2 Cp Cp c Cp 1 c Cp for T T== +? (19) () ( m emf 1 21 cL Cp 1 c Cp for T < T < T (T...

  8. Heat transfer enhancement for turbulent flow through blockages with elongated holes in a rectangular channel 

    E-Print Network [OSTI]

    Lee, Yonghee

    2007-09-17

    In this thesis, turbulent forced convective heat transfer downstream of blockages with elongated holes in a rectangular channel was studied. The rectangular channel has a width-to-height ratio of 12:1. The blockages have the same cross section...

  9. Large-dimension, high-ZT Thermoelectric Nanocomposites for High-Power High-efficiency Waste Heat Recovery for Electricity Generation

    Broader source: Energy.gov [DOE]

    Large-dimension, high-ZT BiTe and Pb-based nanocomposites produced with a low-cost scalable process were used for development and testing of TE module prototypes, and demonstration of a waste heat recovery system

  10. Development and Demonstration of a High Efficiency, Rapid Heating, Low NOx Alternative to Conventional Heating of Round Steel Shapes, Steel Substrate (Strip) and Coil Box Transfer Bars

    SciTech Connect (OSTI)

    Kurek, Harry; Wagner, John

    2010-01-25

    Direct Flame Impingement involves the use of an array of very high-velocity flame jets impinging on a work piece to rapidly heat the work piece. The predominant mode of heat transfer is convection. Because of the locally high rate of heat transfer at the surface of the work piece, the refractory walls and exhaust gases of a DFI furnace are significantly cooler than in conventional radiant heating furnaces, resulting in high thermal efficiency and low NOx emissions. A DFI furnace is composed of a successive arrangement of heating modules through or by which the work piece is conveyed, and can be configured for square, round, flat, and curved metal shapes (e.g., billets, tubes, flat bars, and coiled bars) in single- or multi-stranded applications.

  11. Lattice Boltzmann methods for multiphase flow and phase-change heat transfer

    E-Print Network [OSTI]

    Li, Qing; Kang, Q J; He, Y L; Chen, Q; Liu, Q

    2015-01-01

    Over the past few decades, tremendous progress has been made in the development of particle-based discrete simulation methods versus the conventional continuum-based methods. In particular, the lattice Boltzmann (LB) method has evolved from a theoretical novelty to a ubiquitous, versatile and powerful computational methodology for both fundamental research and engineering applications. It is a kinetic-based mesoscopic approach that bridges the microscales and macroscales, which offers distinctive advantages in simulation fidelity and computational efficiency. Applications of the LB method have been found in a wide range of disciplines including physics, chemistry, materials, biomedicine and various branches of engineering. The present work provides a comprehensive review of the LB method for thermofluids and energy applications, focusing on multiphase flows, thermal flows and thermal multiphase flows with phase change. The review first covers the theoretical framework of the LB method, revealing the existing ...

  12. High Power Hydrogen Injector with Beam Focusing for Plasma Heating

    SciTech Connect (OSTI)

    Deichuli, P.P.; Ivanov, A.A.; Korepanov, S.A.; Mishagin, V.V.; Sorokin, A.V.; Stupishin, N.V

    2005-01-15

    High power neutral beam injector has been developed with the atom energy of 25 keV, a current of 60 A, and several milliseconds pulse duration. Six of these injectors will be used for upgrade of the atomic injection system at central cell of a Gas Dynamic Trap (GDT) device and 2 injectors are planned for SHIP experiment.The injector ion source is based on an arc discharge plasma box. The plasma emitter is produced by a 1 kA arc discharge in hydrogen. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase its efficiency and improve homogeneity of the plasma emitter. The ion beam is extracted by a 4-electrodes ion optical system (IOS). Initial beam diameter is 200 mm. The grids of the IOS have a spherical curvature for geometrical focusing of the beam. The optimal IOS geometry and grid potentials were found with the numerical simulation to provide precise beam formation. The measured angular divergence of the beam is 0.02 rad, which corresponds to the 2.5 cm Gaussian radius of the beam profile measured at focal point.

  13. Nonperiodicity of the flow within the gap of a thermoacoustic couple at high amplitudes

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Nonperiodicity of the flow within the gap of a thermoacoustic couple at high amplitudes Arganthaël arganthael.berson@ec-lyon.fr, philippe.blanc-benon@ec-lyon.fr Abstract: The flow inside a thermoacoustic at high driving amplitudes. Development of vortices is also observed within the gap of a thermoacoustic

  14. Multiwalled carbon nanotube/polydimethylsiloxane composite films as high performance flexible electric heating elements

    SciTech Connect (OSTI)

    Yan, Jing; Jeong, Young Gyu, E-mail: ygjeong@cnu.ac.kr [Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2014-08-04

    High performance elastomeric electric heating elements were prepared by incorporating various contents of pristine multiwalled carbon nanotube (MWCNT) in polydimethylsiloxane (PDMS) matrix by using an efficient solution-casting and curing technique. The pristine MWCNTs were identified to be uniformly dispersed in the PDMS matrix and the electrical percolation of MWCNTs was evaluated to be at ?0.27?wt.?%, where the electrical resistivity of the MWCNT/PDMS composite films dropped remarkably. Accordingly, the composite films with higher MWCNT contents above 0.3?wt.?% exhibit excellent electric heating performance in terms of temperature response rapidity and electric energy efficiency at constant applied voltages. In addition, the composite films, which were thermally stable up to 250?°C, showed excellent heating-cooling cyclic performance, which was associated with operational stability in actual electric heating applications.

  15. UNSAT-H Version 3.0: Unsaturated Soil Water and Heat Flow Model Theory, User Manual, and Examples

    SciTech Connect (OSTI)

    MJ Fayer

    2000-06-12

    The UNSAT-H model was developed at Pacific Northwest National Laboratory (PNNL) to assess the water dynamics of arid sites and, in particular, estimate recharge fluxes for scenarios pertinent to waste disposal facilities. During the last 4 years, the UNSAT-H model received support from the Immobilized Waste Program (IWP) of the Hanford Site's River Protection Project. This program is designing and assessing the performance of on-site disposal facilities to receive radioactive wastes that are currently stored in single- and double-shell tanks at the Hanford Site (LMHC 1999). The IWP is interested in estimates of recharge rates for current conditions and long-term scenarios involving the vadose zone disposal of tank wastes. Simulation modeling with UNSAT-H is one of the methods being used to provide those estimates (e.g., Rockhold et al. 1995; Fayer et al. 1999). To achieve the above goals for assessing water dynamics and estimating recharge rates, the UNSAT-H model addresses soil water infiltration, redistribution, evaporation, plant transpiration, deep drainage, and soil heat flow as one-dimensional processes. The UNSAT-H model simulates liquid water flow using Richards' equation (Richards 1931), water vapor diffusion using Fick's law, and sensible heat flow using the Fourier equation. This report documents UNSAT-H .Version 3.0. The report includes the bases for the conceptual model and its numerical implementation, benchmark test cases, example simulations involving layered soils and plants, and the code manual. Version 3.0 is an, enhanced-capability update of UNSAT-H Version 2.0 (Fayer and Jones 1990). New features include hysteresis, an iterative solution of head and temperature, an energy balance check, the modified Picard solution technique, additional hydraulic functions, multiple-year simulation capability, and general enhancements.

  16. Overall and average local heat transfer from a horizontal cylinder in a gas-fluidized bed with an opposing oscillatory flow

    SciTech Connect (OSTI)

    Pence, D.V. [Univ. of Rhode Island, Kingston, RI (United States). Dept. of Mechanical Engineering and Applied Mechanics; Beasley, D.E. [Clemson Univ., SC (United States). Dept. of Mechanical Engineering

    1996-12-31

    The Pulsed Atmospheric Fluidized Bed Combustor (PAFBC), a hybrid combustor concept that couples a pulsed combustor with an atmospheric bubbling fluidized bed, has technical advantages in energy efficiency and emissions. The present study examines fundamental aspects of heat transfer in this hybrid combustor by measuring the effect of an opposing oscillatory flow on the overall and time-averaged local heat transfer in a laboratory scale bubbling gas-fluidized bed. This opposing secondary flow consisted of a steady mean component and an oscillating component thereby modeling the flow in the tailpipe of a pulsed combustor. Data were acquired for a monodisperse distribution of particles with a mean diameter of 345 {micro}m and total fluidization ratios ranging from 1.1 through 2.7. Overall and time-averaged local heat flux measurements from the surface of a submerged horizontal cylinder show that heat transfer characteristics are significantly altered by an opposing oscillatory flow. Increases in overall heat transfer on the order of 12% were identified for operating conditions with low primary and secondary flow rates and low pulse frequencies. These enhancements were identified to be a consequence of significant localized enhancements. The fundamental trends and magnitude of the particle Nusselt number are effectively characterized by a modified form of the Strouhal number.

  17. High average power laser using a transverse flowing liquid host

    DOE Patents [OSTI]

    Ault, Earl R.; Comaskey, Brian J.; Kuklo, Thomas C.

    2003-07-29

    A laser includes an optical cavity. A diode laser pumping device is located within the optical cavity. An aprotic lasing liquid containing neodymium rare earth ions fills the optical cavity. A circulation system that provides a closed loop for circulating the aprotic lasing liquid into and out of the optical cavity includes a pump and a heat exchanger.

  18. FLIHY EXPERIMENTAL FACILITIES FOR STUDYING OPEN CHANNEL TURBULENT FLOWS AND HEAT TRANSFER

    E-Print Network [OSTI]

    California at Los Angeles, University of

    . The pump station is composed of two centrifugal pumps connected in parallel, capable of pumping 75 L/s of water at maximum speed. The pumps are individually controlled with variable speed inverters to allow feeds the fluid to the pumps. 3. Built-in diagnostics tools include the flow meter, thermocouples

  19. Effect of wall conduction on heat transfer for turbulent flow in a circular tube 

    E-Print Network [OSTI]

    Lin, Yie-Kuang

    1980-01-01

    ) then ~ y+) 1+ g-7 x? ~? CmR. ~&r I'g g x I, & " pig. p()c)} f so as tm Lr=b rnn ? y Z. C R?(v)e~P( ? P X ) ~ M o (14) 2 where P =1, b. = (i+1) w. m m, ' i i+1 + + F (x )= (1 ? exp(-P x ) }/P 0 Ill Itl + . +i + F, (x )= (x -iF, (x )}/P...") &)(. ? Gz & ( 0 0 (K, ( L ) Zi( ~ )+ Z, (" L ) K, ( L')j/ J (i+2-, 7. X )C. S Z X dX (23) Heat Exchan e Between the Fluid and the Solid Wall (i) Constant Heat Flux The following relations are applicable at the fluid-solid interface (24) Using Eq...

  20. Subcooled flow boiling of fluorocarbons

    E-Print Network [OSTI]

    Murphy, Richard Walter

    1971-01-01

    A study was conducted of heat transfer and hydrodynamic behavior for subcooled flow boiling of Freon-113, one of a group of fluorocarbons suitable for use in cooling of high-power-density electronic components. Problems ...

  1. Candidate alloys for cost-effective, high-efficiency, high-temperature compact/foil heat-exchangers

    SciTech Connect (OSTI)

    Evans, Neal D; Maziasz, Philip J; Shingledecker, John P; Pint, Bruce A; Yamamoto, Yukinori

    2007-01-01

    Solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC) systems operate at high temperatures (up to 1000 C and 650 C, respectively), which makes them especially attractive sources for combined heat and power (CHP) cogeneration. However, improvements in the efficiency of heat exchange in these fuel cells require both development and careful processing of advanced cost-effective alloys for use in such high-temperature service conditions. The high-temperature properties of both sheet and foil forms of several alloys being considered for use in compact heat-exchangers (recuperators) have been characterized. Mechanical and creep-rupture testing, oxidation studies, and microstructural studies have been performed on commercially available sheet and foil forms of alloy 347, alloys 625, HR230, HR120, and the new AL20-25+Nb. These studies have led to a mechanistic understanding of the responses of these alloys to anticipated service conditions, and suggest that these alloys developed for gas- and micro-turbine recuperator applications are also suitable for use in fuel cell heat-exchangers. Additional work is still required to achieve foil forms with creep life comparable to thicker-section wrought product forms of the same alloys.

  2. Rotor bore and turbine rotor wheel/spacer heat exchange flow circuit

    DOE Patents [OSTI]

    Caruso, Philip M. (Selkirk, NY); Eldrid, Sacheverel Quentin (Saratoga Springs, NY); Ladhani, Azad A. (Niskayuna, NY); DeMania, Alan Richard (Niskayuna, NY); Palmer, Gene David (Clifton Park, NY); Wilson, Ian David (Clifton Park, NY); Rathbun, Lisa Shirley (Scotia, NY); Akin, Robert Craig (Schenectady, NY)

    2002-01-01

    In a turbine having closed-circuit steam-cooling passages about the rim of the rotor during steady-state operation, compressor discharge air is supplied to the rotor bore for passage radially outwardly into the wheel space cavities between the wheels and spacers. Communicating slots and channels in the spacers and wheels at circumferentially spaced positions enable egress of the compressor discharge air into the hot gas flow path. At turbine startup, cooling air flows through the closed-circuit steam passages to cool the outer rim of the rotor while compressor discharge air pre-warms the wheels and spacers. At steady-state, cooling steam is supplied in the closed-circuit steam-cooling passages and compressor discharge air is supplied through the bore and into the wheel space cavities to cool the rotor.

  3. Numerical simulation of flow and heat transfer of internal cooling passage in gas turbine blade 

    E-Print Network [OSTI]

    Su, Guoguang

    2007-04-25

    for efficient energy utilization; one of the most powerful means of achieving higher efficiency in industrial gas turbine engines is to raise the turbine inlet temperature (TIT). Sophisticated cooling techniques must be employed to cool the components... for momentum, energy, and turbulence quantities are solved in curvilinear, body-fitted coordinates using the finite-analytic method. 2.1 The Governing Equation and Chimera Method For unsteady incompressible flow, the continuty equation and momentum...

  4. Development of High Efficiency Carbon Dioxide Commercial Heat Pump Water Heater

    SciTech Connect (OSTI)

    Michael PETERSEN; Chad D. BOWERS; Stefan ELBEL; Pega HRNJAK

    2012-07-01

    Although heat pump water heaters are today widely accepted in both Japan and Europe, where energy costs are high and government incentives for their use exist, acceptance of such products in the US has been limited. While this trend is slowly changing with the introduction of heat pump water heaters into the residential market, but acceptance remains low in the commercial sector. The objective of the presented work is the development of a high efficiency R744 heat pump water heater for commercial applications with effective utilization of the cooling capability for air conditioning and/or refrigeration. The ultimate goal is to achieve total system COP of up to 8. This unit will be targeted at commercial use where some cooling load is typically needed year round, such as restaurants, hotels, nursing homes, and hospitals. This paper presents the performance results from the development of four R744 commercial heat pump water heater packages of approximately 35 kW and comparison to a commercially available baseline R134a unit of the same capacity and footprint. In addition, the influences of an internal heat exchanger and an enhanced evaporator on the system performance are described and recommendations are made for further improvements of the R744 system.

  5. Promoting isothermal martensite formation by high temperature heat treatments in a precipitation hardening austenitic stainless steel

    E-Print Network [OSTI]

    Cambridge, University of

    Promoting isothermal martensite formation by high temperature heat treatments in a precipitation hardening austenitic stainless steel David San Martín* and Carlos García-Mateo MATERALIA Group, Dept mechanical properties, the steel investigated (12Cr-9Ni-4Mo-2Cu-1Ti) is solution treated and cooled down

  6. Improved Heat Transfer and Performance of High Intensity Combustion Systems for Reformer Furnace Applications 

    E-Print Network [OSTI]

    Williams, F. D. M.; Kondratas, H. M.

    1983-01-01

    Developments over the past fifteen years have evolved new short flame, high intensity (1,000,000 BTU/HR/ft3 ) combustion systems for industrial uses. Such systems produce a more uniform and higher heat flux than conventional low intensity systems...

  7. The high-energy-density counterpropagating shear experiment and turbulent self-heating

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

    Doss, F. W.; Fincke, J. R.; Loomis, E. N.; Welser-Sherrill, L.; Flippo, K. A.

    2013-12-06

    The counterpropagating shear experiment has previously demonstrated the ability to create regions of shockdriven shear, balanced symmetrically in pressure and experiencing minimal net drift. This allows for the creation of a high-Mach-number high-energy-density shear environment. New data from the counterpropagating shear campaign is presented, and both hydrocode modeling and theoretical analysis in the context of a Reynolds-averaged-Navier-Stokes model suggest turbulent dissipation of energy from the supersonic flow bounding the layer is a significant driver in its expansion. A theoretical minimum shear flow Mach number threshold is suggested for substantial thermal-turbulence coupling.

  8. Industrial Waste Heat Recovery Using Heat Pipes 

    E-Print Network [OSTI]

    Ruch, M. A.

    1981-01-01

    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...

  9. Technology Development Roadmap for the Advanced High Temperature Reactor Secondary Heat Exchanger

    SciTech Connect (OSTI)

    P. Sabharwall; M. McCllar; A. Siahpush; D. Clark; M. Patterson; J. Collins

    2012-09-01

    This Technology Development Roadmap (TDRM) presents the path forward for deploying large-scale molten salt secondary heat exchangers (MS-SHX) and recognizing the benefits of using molten salt as the heat transport medium for advanced high temperature reactors (AHTR). This TDRM will aid in the development and selection of the required heat exchanger for: power production (the first anticipated process heat application), hydrogen production, steam methane reforming, methanol to gasoline production, or ammonia production. This TDRM (a) establishes the current state of molten salt SHX technology readiness, (b) defines a path forward that systematically and effectively tests this technology to overcome areas of uncertainty, (c) demonstrates the achievement of an appropriate level of maturity prior to construction and plant operation, and (d) identifies issues and prioritizes future work for maturing the state of SHX technology. This study discusses the results of a preliminary design analysis of the SHX and explains the evaluation and selection methodology. An important engineering challenge will be to prevent the molten salt from freezing during normal and off-normal operations because of its high melting temperature (390°C for KF ZrF4). The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The need for efficiency, compactness, and safety challenge the capabilities of existing heat exchanger technology. The description of potential heat exchanger configurations or designs (such as printed circuit, spiral or helical coiled, ceramic, plate and fin, and plate type) were covered in an earlier report (Sabharwall et al. 2011). Significant future work, much of which is suggested in this report, is needed before the benefits and full potential of the AHTR can be realized. The execution of this TDRM will focuses research efforts on the near-term qualification, selection, or maturation strategy as detailed in this report. Development of the integration methodology feasibility study, along with research and development (R&D) needs, are ongoing tasks that will be covered in the future reports as work progresses. Section 2 briefly presents the integration of AHTR technology with conventional chemical industrial processes., See Idaho National Laboratory (INL) TEV-1160 (2011) for further details

  10. High performance electrodes in vanadium redox flow batteries through oxygen-enriched thermal activation

    E-Print Network [OSTI]

    Mench, Matthew M.

    National Laboratory, Oak Ridge, TN 37831, USA h i g h l i g h t s Thermal activation of carbon paper: Vanadium redox flow battery Carbon paper Kinetics Surface area Thermal activation Electrode a b s t r a cHigh performance electrodes in vanadium redox flow batteries through oxygen-enriched thermal

  11. A flow field enabling operating direct methanol fuel cells with highly concentrated methanol

    E-Print Network [OSTI]

    Zhao, Tianshou

    the cathode potential, but also leads to a waste of fuel, lowering the overall efficiency of fuel cell [5A flow field enabling operating direct methanol fuel cells with highly concentrated methanol Q. Xu Available online 8 October 2010 Keywords: Fuel cells Direct methanol fuel cells Concentrated methanol Flow

  12. Flow over rough topography. A preliminary study with high resolution topography at Ormen Lange

    E-Print Network [OSTI]

    Avlesen, Helge

    Flow over rough topography. A preliminary study with high resolution topography at Ormen Lange not able to march as long in time as desired, due to stability issues. On the given topography for selected horizontal sections, after im- posing a constant velocity flow over the given topography

  13. Interplay between Dephasing and Geometry and Directed Heat Flow in Exciton Transfer Complexes

    E-Print Network [OSTI]

    Dubi, Yonatan

    2015-01-01

    The striking efficiency of energy transfer in natural photosynthetic systems and the recent evidence of long-lived quantum coherence in biological light harvesting complexes has triggered much excitement, due to the evocative possibility that these systems - essential to practically all life on earth -- use quantum mechanical effects to achieve optimal functionality. A large body of theoretical work has addressed the role of local environments in determining the transport properties of excitons in photosynthetic networks and the survival of quantum coherence in a classical environment. Nonetheless, understanding the connection between quantum coherence, exciton network geometry and energy transfer efficiency remains a challenge. Here we address this connection from the perspective of heat transfer within the exciton network. Using a non-equilibrium open quantum system approach and focusing on the Fenna-Matthews-Olson complex, we demonstrate that finite local dephasing can be beneficial to the overall power ou...

  14. Heat Transfer Characteristics of Sulfur and Sulfur Diluted with Hydrogen Sulfide Flowing Through Circular Tubes 

    E-Print Network [OSTI]

    Stone, Porter Walwyn

    1960-01-01

    is the tube length. Letting q = q, to obtain a relationship for equivalent heat transfer, gives h d L 6t s w w w h d L ht W s s s Substituting into the equation above, 0. 8 d 0. 2 w w w =H s w d L 0. 8d 0. 2 s s s v w s This may be simpbified... isolated. The derivation of the "geometry relationship" follows that outlined in the previous section. h ? 1 30087 d ~P c ql/3 k x 0 023 v 0. 8 d -0. 2 pr -2/3 ( ~) -0. 2 (Io w'ww wow wpw 0 3354 ( P ) 1/3 k 2/3 Pr 0/3 ( P) 0. 2 1/3d -1/3 s s s s w...

  15. Mold, flow, and economic considerations in high temperature precision casting

    E-Print Network [OSTI]

    Humbert, Matthew S

    2013-01-01

    Casting high temperature alloys that solidify through a noticeable two phase region, specifically platinum-ruthenium alloys, is a particularly challenging task due to their high melting temperature and this necessitates ...

  16. Alternative Passive Decay-Heat Systems for the Advanced High-Temperature Reactor

    SciTech Connect (OSTI)

    Forsberg, Charles W.

    2006-07-01

    The Advanced High-Temperature Reactor (AHTR) is a low-pressure, liquid-salt-cooled high-temperature reactor for the production of electricity and hydrogen. The high-temperature (950 deg C) variant is defined as the liquid-salt-cooled very high-temperature reactor (LS-VHTR). The AHTR has the same safety goals and uses the same graphite-matrix coated particle fuel as do modular high-temperature gas-cooled reactors. However, the large AHTR power output [2400 to 4000 MW(t)] implies the need for a different type of passive decay-heat removal system. Because the AHTR is a low-pressure, liquid-cooled reactor like sodium-cooled reactors, similar types of decay-heat-removal systems can be used. Three classes of passive decay heat removal systems have been identified: the reactor vessel auxiliary cooling system which is similar to that proposed for the General Electric S-PRISM sodium-cooled fast reactor; the direct reactor auxiliary cooling system, which is similar to that used in the Experimental Breeder Reactor-II; and a new pool reactor auxiliary cooling system. These options are described and compared. (author)

  17. Impact of unsteady flow processes on the performance of a high speed axial flow compressor

    E-Print Network [OSTI]

    Botros, Barbara Brenda

    2008-01-01

    This thesis examines the unsteady interactions between blade rows in a high Mach number, highly-loaded compressor stage. Two straight vane/rotor configurations with different axial spacing between vane and rotor are ...

  18. Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger

    DOE Patents [OSTI]

    Berry, Gregory F. (Naperville, IL); Minkov, Vladimir (Skokie, IL); Petrick, Michael (Joliet, IL)

    1988-01-01

    A magnetohydrodynamic (MHD) power generating system in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.

  19. Open-cycle magnetohydrodynamic power plant based upon direct-contact closed-loop high-temperature heat exchanger

    DOE Patents [OSTI]

    Berry, G.F.; Minkov, V.; Petrick, M.

    1981-11-02

    A magnetohydrodynamic (MHD) power generating system is described in which ionized combustion gases with slag and seed are discharged from an MHD combustor and pressurized high temperature inlet air is introduced into the combustor for supporting fuel combustion at high temperatures necessary to ionize the combustion gases, and including a heat exchanger in the form of a continuous loop with a circulating heat transfer liquid such as copper oxide. The heat exchanger has an upper horizontal channel for providing direct contact between the heat transfer liquid and the combustion gases to cool the gases and condense the slag which thereupon floats on the heat transfer liquid and can be removed from the channel, and a lower horizontal channel for providing direct contact between the heat transfer liquid and pressurized air for preheating the inlet air. The system further includes a seed separator downstream of the heat exchanger.

  20. Fabrication and Design Aspects of High-Temperature Compact Diffusion Bonded Heat Exchangers

    SciTech Connect (OSTI)

    Mylavarapu, Sai K.; Sun, Xiaodong; Christensen, Richard N.; Glosup, Richard E.; Unocic, Raymond R

    2012-01-01

    The very high temperature reactor (VHTR), using gas-cooled reactor technology, is one of the six reactor concepts selected by the Generation IV International Forum and is anticipated to be the reactor type for the next generation nuclear plant (NGNP). In this type of reactor with an indirect power cycle system, a high-temperature and high integrity intermediate heat exchanger (IHX) with high effectiveness is required to efficiently transfer the core thermal output to secondary fluid for electricity production, process heat, or hydrogen cogeneration. The current Technology Readiness Level status issued by NGNP to all components associated with the IHX for reactor core outlet temperatures of 750-800oC is 3 on a scale of 1 to 10 with 10 being the most ready. At present, there is no proven high-temperature IHX concept for VHTRs. Amongst the various potential IHX concepts available, diffusion bonded heat exchangers (henceforth called printed circuit heat exchangers, or PCHEs) appear promising for NGNP applications. The design and fabrication of this key component of NGNP is the primary focus of this paper. In the current study, two PCHEs were fabricated using Alloy 617 plates and will be experimentally investigated for their thermal-hydraulic performance in a high-temperature helium test facility (HTHF). The HTHF was primarily designed and constructed to test the thermal-hydraulic performance of PCHEs The test facility is primarily of Alloy 800H construction and is designed to facilitate experiments at temperatures and pressures up to 800oC and 3 MPa, respectively. The PCHE fabrication related processes, i.e., photochemical machining and diffusion bonding are briefly discussed for Alloy 617 plates. Diffusion bonding of Alloy 617 plates with and without a Ni interlayer is discussed. Furthermore, preliminary microstructural and mechanical characterization studies of representative diffusion bonded Alloy 617 specimens are presented.

  1. Local wall heat flux/temperature meter for convective flow and method of utilizing same

    DOE Patents [OSTI]

    Boyd, Ronald D.; Ekhlassi, Ali; Cofie, Penrose

    2004-11-30

    According to one embodiment of the invention, a method includes providing a conduit having a fluid flowing therethrough, disposing a plurality of temperature measurement devices inside a wall of the conduit, positioning at least some of the temperature measurement devices proximate an inside surface of the wall of the conduit, positioning at least some of the temperature measurement devices at different radial positions at the same circumferential location within the wall, measuring a plurality of temperatures of the wall with respective ones of the temperature measurement devices to obtain a three-dimensional temperature topology of the wall, determining the temperature dependent thermal conductivity of the conduit, and determining a multi-dimensional thermal characteristic of the inside surface of the wall of the conduit based on extrapolation of the three-dimensional temperature topology and the temperature dependent thermal conductivities.

  2. Geometric Multigrid Methods for Flow Problems in Highly Heterogeneous Porous Media 

    E-Print Network [OSTI]

    Mao, Youli

    2014-06-05

    In this dissertation, we develop geometric multigrid methods for the finite element approximation of flow problems (e:g:, Stokes, Darcy and Brinkman models) in highly heterogeneous porous media. Our method is based on ...

  3. Congestion control schemes for single and parallel TCP flows in high bandwidth-delay product networks 

    E-Print Network [OSTI]

    Cho, Soohyun

    2006-08-16

    In this work, we focus on congestion control mechanisms in Transmission Control Protocol (TCP) for emerging very-high bandwidth-delay product networks and suggest several congestion control schemes for parallel and single-flow ...

  4. Heat pipe radiation cooling (HPRC) for high-speed aircraft propulsion. Phase 2 (feasibility) final report

    SciTech Connect (OSTI)

    Martin, R.A.; Merrigan, M.A.; Elder, M.G.; Sena, J.T.; Keddy, E.S.; Silverstein, C.C.

    1994-03-25

    The National Aeronautics and Space Administration (NASA), Los Alamos National Laboratory (Los Alamos), and CCS Associates are conducting the Heat Pipe Radiation Cooling (HPRC) for High-Speed Aircraft Propulsion program to determine the advantages and demonstrate the feasibility of using high-temperature heat pipes to cool hypersonic engine components. This innovative approach involves using heat pipes to transport heat away from the combustor, nozzle, or inlet regions, and to reject it to the environment by thermal radiation from adjacent external surfaces. HPRC is viewed as an alternative (or complementary) cooling technique to the use of pumped cryogenic or endothermic fuels to provide regenerative fuel or air cooling of the hot surfaces. The HPRC program has been conducted through two phases, an applications phase and a feasibility phase. The applications program (Phase 1) included concept and assessment analyses using hypersonic engine data obtained from US engine company contacts. The applications phase culminated with planning for experimental verification of the HPRC concept to be pursued in a feasibility program. The feasibility program (Phase 2), recently completed and summarized in this report, involved both analytical and experimental studies.

  5. User's Guide of TOUGH2-EGS. A Coupled Geomechanical and Reactive Geochemical Simulator for Fluid and Heat Flow in Enhanced Geothermal Systems Version 1.0

    SciTech Connect (OSTI)

    Fakcharoenphol, Perapon; Xiong, Yi; Hu, Litang; Winterfeld, Philip H.; Xu, Tianfu; Wu, Yu-Shu

    2013-05-01

    TOUGH2-EGS is a numerical simulation program coupling geomechanics and chemical reactions for fluid and heat flows in porous media and fractured reservoirs of enhanced geothermal systems. The simulator includes the fully-coupled geomechanical (THM) module, the fully-coupled geochemical (THC) module, and the sequentially coupled reactive geochemistry (THMC) module. The fully-coupled flow-geomechanics model is developed from the linear elastic theory for the thermo-poro-elastic system and is formulated with the mean normal stress as well as pore pressure and temperature. The chemical reaction is sequentially coupled after solution of flow equations, which provides the flow velocity and phase saturation for the solute transport calculation at each time step. In addition, reservoir rock properties, such as porosity and permeability, are subjected to change due to rock deformation and chemical reactions. The relationships between rock properties and geomechanical and chemical effects from poro-elasticity theories and empirical correlations are incorporated into the simulator. This report provides the user with detailed information on both mathematical models and instructions for using TOUGH2-EGS for THM, THC or THMC simulations. The mathematical models include the fluid and heat flow equations, geomechanical equation, reactive geochemistry equations, and discretization methods. Although TOUGH2-EGS has the capability for simulating fluid and heat flows coupled with both geomechanical and chemical effects, it is up to the users to select the specific coupling process, such as THM, THC, or THMC in a simulation. There are several example problems illustrating the applications of this program. These example problems are described in details and their input data are presented. The results demonstrate that this program can be used for field-scale geothermal reservoir simulation with fluid and heat flow, geomechanical effect, and chemical reaction in porous and fractured media.

  6. Large eddy simulation of atmospheric boundary layer flow in urban terrain : implications for transport of pollution and heat

    E-Print Network [OSTI]

    Sun, Long

    2011-01-01

    such as the urban heat island and increase in urban energyloads and the urban heat island-the effects of albedo,modeling of urban heat islands. Final report prepared by

  7. Large eddy simulation of atmospheric boundary layer flow in urban terrain : implications for transport of pollution and heat

    E-Print Network [OSTI]

    Sun, Long

    2011-01-01

    loads and the urban heat island-the effects of albedo,modeling of urban heat islands. Final report prepared byeffects such as the urban heat island and increase in urban

  8. The Influence of Proposed Repository Thermal Load on Multiphase Flow and Heat Transfer in the Unsaturated Zone of Yucca Mountain

    E-Print Network [OSTI]

    Wu, Y.-S.; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, G.S.

    2006-01-01

    two-phase zone, is the heat-pipe (i.e. , a zone of constant4a), when there is a heat pipe just above the emplacementduring ventilation, the heat-pipe signature is absent in

  9. Large eddy simulation of atmospheric boundary layer flow in urban terrain : implications for transport of pollution and heat

    E-Print Network [OSTI]

    Sun, Long

    2011-01-01

    loads and the urban heat island-the effects of albedo,modeling of urban heat islands. Final report prepared byespecially the urban heat island (UHI) and urban air

  10. The effect of velocity boundary conditions on the heat transfer and flow topology in two-dimensional Rayleigh-B\\'enard convection

    E-Print Network [OSTI]

    van der Poel, Erwin P; Verzicco, Roberto; Lohse, Detlef

    2015-01-01

    The effect of various velocity boundary condition is studied in two-dimensional Rayleigh-B\\'enard convection. Combinations of no-slip, stress-free and periodic boundary conditions are used on both the sidewalls and the horizontal plates. For the studied Rayleigh numbers Ra between $10^8$ and $10^{11}$ the heat transport is lower for $\\Gamma = 0.33$ than for $\\Gamma = 1$ in case of no-slip sidewalls. This is surprisingly opposite for stress-free sidewalls, where the heat transport increases for lower aspect-ratio. In wider cells the aspect-ratio dependence is observed to disappear for $\\text{Ra} \\ge 10^{10}$. Two distinct flow types with very different dynamics can be seen, mostly dependent on the plate velocity boundary condition, namely roll-like flow and horizontal zonal flow, which have a substantial effect on the dynamics and heat transport in the system. The predominantly horizontal zonal flow suppresses heat flux and is observed for stress-free and asymmetric plates. Low aspect-ratio periodic sidewall s...

  11. Interannual Changes in Seasonal Ground Freezing and Near-surface Heat Flow Beneath Bottom-fast Ice in the Near-shore Zone, Mackenzie Delta, NWT, Canada

    E-Print Network [OSTI]

    Moorman, Brian

    Interannual Changes in Seasonal Ground Freezing and Near-surface Heat Flow Beneath Bottom-fast Ice Resources Canada, Dartmouth, Nova Scotia, Canada ABSTRACT Interannual changes in seasonal ground freezing. KEY WORDS: seasonal ground freezing; permafrost; bottom-fast ice; Mackenzie Delta INTRODUCTION Arctic

  12. VOL. 167 -NO. 12 HEATS OF EXCHANGE MEASURED BY FLOW CALORIMETRY 777 kaolinitic soil clay that he derived from the tem-

    E-Print Network [OSTI]

    Ma, Lena

    #12;#12;#12;#12;VOL. 167 -NO. 12 HEATS OF EXCHANGE MEASURED BY FLOW CALORIMETRY 777 kaolinitic soil any reported values for K/Ca exchange. After look- ing at Udo's data more carefully,however, we be,-', not the 54.5 kJ mol,-' orig- inallyreported. If our calculation is correct,Udo's enthalpy for K/Ca exchange

  13. 6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi'an, China, 11-15 July 2009

    E-Print Network [OSTI]

    Khandekar, Sameer

    from a variety of sources including fossil fuels (coal, natural gas, LPG, gasoline, diesel, methane in the process. Use of natural gas or naphtha as a raw material is an industrial process. Typical reactions6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi

  14. Experimental and numerical investigation of turbulent flow and heat (mass) transfer in a two-pass trapezoidal channel with turbulence promoters 

    E-Print Network [OSTI]

    Oh, Sung Hyuk

    2009-05-15

    , as results of the secondary flow induced by the (–) 60º ribs. The overall average heat (mass) transfer for the larger inlet cases was always higher than that for the smaller inlet cases in the ribbed trapezoidal channel. Considering the thermal performance...

  15. Flow-induced chain scission as a physical route to narrowly distributed, high molar mass polymers

    E-Print Network [OSTI]

    Barron, Annelise E.

    Flow-induced chain scission as a physical route to narrowly distributed, high molar mass polymers Abstract We present data showing a substantial narrowing of the polydispersity index (PDI) of high polymers experiments, semi-dilute aqueous solutions of high-molar mass, polydisperse polymers (PDI . 1.4) were injected

  16. Simulation of High Density Pedestrian Flow: Microscopic Model

    E-Print Network [OSTI]

    Dridi, Mohamed H

    2015-01-01

    In recent years modelling crowd and evacuation dynamics has become very important, with increasing huge numbers of people gathering around the world for many reasons and events. The fact that our global population grows dramatically every year and the current public transport systems are able to transport large amounts of people, heightens the risk of crowd panic or crush. Pedestrian models are based on macroscopic or microscopic behaviour. In this paper, we are interested in developing models that can be used for evacuation control strategies. This model will be based on microscopic pedestrian simulation models, and its evolution and design requires a lot of information and data. The people stream will be simulated, based on mathematical models derived from empirical data about pedestrian flows. This model is developed from image data bases, so called empirical data, taken from a video camera or data obtained using human detectors. We consider the individuals as autonomous particles interacting through socia...

  17. MHD EFFECTS ON HEAT TRANSFER IN A MOLTEN SALT BLANKET Sergey Smolentsev, Reza Miraghaie, Mohamed Abdou

    E-Print Network [OSTI]

    Abdou, Mohamed

    MHD EFFECTS ON HEAT TRANSFER IN A MOLTEN SALT BLANKET Sergey Smolentsev, Reza Miraghaie, Mohamed-mail (Sergey Smolentsev): Sergey@fusion.ucla.edu Heat transfer in closed channel flows of molten salts (MS of the concept is that the flows in the FW channels are turbulent to provide a high heat transfer coefficient

  18. Highly-Efficient Thermoelectronic Conversion of Solar Energy and Heat into Electric Power

    E-Print Network [OSTI]

    Meir, S; Geballe, T H; Mannhart, J

    2013-01-01

    Electric power may, in principle, be generated in a highly efficient manner from heat created by focused solar irradiation, chemical combustion, or nuclear decay by means of thermionic energy conversion. As the conversion efficiency of the thermionic process tends to be degraded by electron space charges, the efficiencies of thermionic generators have amounted to only a fraction of those fundamentally possible. We show that this space-charge problem can be resolved by shaping the electric potential distribution of the converter such that the static electron space-charge clouds are transformed into an output current. Although the technical development of practical generators will require further substantial efforts, we conclude that a highly efficient transformation of heat to electric power may well be achieved.

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

    SciTech Connect (OSTI)

    2011-11-21

    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.

  20. Two-dimensional model of the air flow and temperature distribution in a cavity-type heat receiver of a solar stirling engine

    SciTech Connect (OSTI)

    Makhkamov, K.K.; Ingham, D.B.

    1999-11-01

    A theoretical study on the air flow and temperature in the heat receiver, affected by free convection, of a Stirling Engine for a Dish/Stirling Engine Power System is presented. The standard {kappa}-{epsilon} turbulence model for the fluid flow has been used and the boundary conditions employed were obtained using a second level mathematical model of the Stirling Engine working cycle. Physical models for the distribution of the solar insolation from the Concentrator on the bottom and side walls of the cavity-type heat receiver have been taken into account. The numerical results show that most of the heat losses in the receiver are due to re-radiation from the cavity and conduction through the walls of the cavity. It is in the region of the boundary of the input window of the heat receiver where there is a sensible reduction in the temperature in the shell of the heat exchangers and this is due to the free convection of the air. Further, the numerical results show that convective heat losses increase with decreasing tilt angle.

  1. A visualization comparison of convective flow boiling heat transfer augmentation devices 

    E-Print Network [OSTI]

    Lundy, Brian Franklin

    1998-01-01

    of 9.50, 7.2 1, and 3.72, a static mixer, and a circumferentailly wrapped wire screen were compared with bare tube data to ascertain the qualitative effects of these devices. Visualization experiments using high resolution video techniques were...

  2. Retrograde Transvenous Ethanol Embolization of High-flow Peripheral Arteriovenous Malformations

    SciTech Connect (OSTI)

    Linden, Edwin van der; Baalen, Jary M. van; Pattynama, Peter M. T.

    2012-08-15

    Purpose: To report the clinical efficiency and complications in patients treated with retrograde transvenous ethanol embolization of high-flow peripheral arteriovenous malformations (AVMs). Retrograde transvenous ethanol embolization of high-flow AVMs is a technique that can be used to treat AVMs with a dominant outflow vein whenever conventional interventional procedures have proved insufficient. Methods: This is a retrospective study of the clinical effectiveness and complications of retrograde embolization in five patients who had previously undergone multiple arterial embolization procedures without clinical success. Results: Clinical outcomes were good in all patients but were achieved at the cost of serious, although transient, complications in three patients. Conclusion: Retrograde transvenous ethanol embolization is a highly effective therapy for high-flow AVMs. However, because of the high complication rate, it should be reserved as a last resort, to be used after conventional treatment options have failed.

  3. Method For Enhanced Gas Monitoring In High Density Flow Streams

    DOE Patents [OSTI]

    Von Drasek, William A. (Oak Forest, IL); Mulderink, Kenneth A. (Countryside, IL); Marin, Ovidiu (Lisle, IL)

    2005-09-13

    A method for conducting laser absorption measurements in high temperature process streams having high levels of particulate matter is disclosed. An impinger is positioned substantially parallel to a laser beam propagation path and at upstream position relative to the laser beam. Beam shielding pipes shield the beam from the surrounding environment. Measurement is conducted only in the gap between the two shielding pipes where the beam propagates through the process gas. The impinger facilitates reduced particle presence in the measurement beam, resulting in improved SNR (signal-to-noise) and improved sensitivity and dynamic range of the measurement.

  4. Expanded microchannel heat exchanger: design, fabrication and preliminary experimental test

    E-Print Network [OSTI]

    Denkenberger, David C; Pearce, Joshua M; Zhai, John; 10.1177/0957650912442781

    2012-01-01

    This paper first reviews non-traditional heat exchanger geometry, laser welding, practical issues with microchannel heat exchangers, and high effectiveness heat exchangers. Existing microchannel heat exchangers have low material costs, but high manufacturing costs. This paper presents a new expanded microchannel heat exchanger design and accompanying continuous manufacturing technique for potential low-cost production. Polymer heat exchangers have the potential for high effectiveness. The paper discusses one possible joining method - a new type of laser welding named "forward conduction welding," used to fabricate the prototype. The expanded heat exchanger has the potential to have counter-flow, cross-flow, or parallel-flow configurations, be used for all types of fluids, and be made of polymers, metals, or polymer-ceramic precursors. The cost and ineffectiveness reduction may be an order of magnitude or more, saving a large fraction of primary energy. The measured effectiveness of the prototype with 28 micro...

  5. Direct containment heating and aerosol generation during high-pressure-melt expulsion experiments

    SciTech Connect (OSTI)

    Tarbell, W.W.; Brockmann, J.E.; Washington, K.E.; Pilch, M.; Marx, K.D.

    1988-01-01

    Severe nuclear plant accidents can involve the degradation of the reactor core while the primary coolant system remains pressurized. Molten fuel reaching the lower head of the reactor pressure vessel (RPV) may attack and fail the instrument guide tube penetrations, allowing the tube to be expelled from the vessel. The resulting aperture allows the molten fuel to be ejected into the cavity, followed by the blowdown of the contents of the primary system (high-pressure-melt ejection). Entrainment of the core debris in the cavity by the blowdown gases may cause high-temperature fuel particles to be carried into the containment building. Energy exchange between the particles and the atmosphere may cause heating and pressurizing of the containment (direct containment heating (DCH)). The complex phenomena associated with direct containment heating accident sequences are not well understood. This work describes a series of four experiments that have been performed to study and quantify the processes involved. The data from the experiments are used to guide the development of computer models to describe the response of containments under accident conditions.

  6. Joule heat generation in thermionic cathodes of high-pressure arc discharges

    SciTech Connect (OSTI)

    Benilov, M. S.; Cunha, M. D.

    2013-02-14

    The nonlinear surface heating model of plasma-cathode interaction in high-pressure arcs is extended to take into account the Joule effect inside the cathode body. Calculation results are given for different modes of current transfer to tungsten cathodes of different configurations in argon plasmas of atmospheric or higher pressures. Special attention is paid to analysis of energy balances of the cathode and the near-cathode plasma layer. In all the cases, the variation of potential inside the cathode is much smaller than the near-cathode voltage drop. However, this variation can be comparable to the volt equivalent of the energy flux from the plasma to the cathode and then the Joule effect is essential. Such is the case of the diffuse and mixed modes on rod cathodes at high currents, where the Joule heating causes a dramatic change of thermal and electrical regimes of the cathode. The Joule heating has virtually no effect over characteristics of spots on rod and infinite planar cathodes.

  7. Formulation and sequential numerical algorithms of coupled fluid/heat flow and geomechanics for multiple porosity materials

    E-Print Network [OSTI]

    Kim, J.

    2014-01-01

    Settari A. Modeling of geomechanics in naturally fracturedway coupled fluid flow and geomechanics in hydrate deposits.for coupled flow and geomechanics: Drained and undrained

  8. Investigation on the Core Bypass Flow in a Very High Temperature Reactor

    SciTech Connect (OSTI)

    Hassan, Yassin

    2013-10-22

    Uncertainties associated with the core bypass flow are some of the key issues that directly influence the coolant mass flow distribution and magnitude, and thus the operational core temperature profiles, in the very high-temperature reactor (VHTR). Designers will attempt to configure the core geometry so the core cooling flow rate magnitude and distribution conform to the design values. The objective of this project is to study the bypass flow both experimentally and computationally. Researchers will develop experimental data using state-of-the-art particle image velocimetry in a small test facility. The team will attempt to obtain full field temperature distribution using racks of thermocouples. The experimental data are intended to benchmark computational fluid dynamics (CFD) codes by providing detailed information. These experimental data are urgently needed for validation of the CFD codes. The following are the project tasks: • Construct a small-scale bench-top experiment to resemble the bypass flow between the graphite blocks, varying parameters to address their impact on bypass flow. Wall roughness of the graphite block walls, spacing between the blocks, and temperature of the blocks are some of the parameters to be tested. • Perform CFD to evaluate pre- and post-test calculations and turbulence models, including sensitivity studies to achieve high accuracy. • Develop the state-of-the art large eddy simulation (LES) using appropriate subgrid modeling. • Develop models to be used in systems thermal hydraulics codes to account and estimate the bypass flows. These computer programs include, among others, RELAP3D, MELCOR, GAMMA, and GAS-NET. Actual core bypass flow rate may vary considerably from the design value. Although the uncertainty of the bypass flow rate is not known, some sources have stated that the bypass flow rates in the Fort St. Vrain reactor were between 8 and 25 percent of the total reactor mass flow rate. If bypass flow rates are on the high side, the quantity of cooling flow through the core may be considerably less than the nominal design value, causing some regions of the core to operate at temperatures in excess of the design values. These effects are postulated to lead to localized hot regions in the core that must be considered when evaluating the VHTR operational and accident scenarios.

  9. Measurement and computation of heat transfer in high-pressure compressor drum geometries with axial throughflow

    SciTech Connect (OSTI)

    Long, C.A.; Morse, A.P.; Tucker, P.G.

    1997-01-01

    This paper makes comparisons between CFD computations and experimental measurements of heat transfer for the axial throughflow of cooling air in a high-pressure compressor spool rig and a plane cavity rig. The heat transfer measurements are produced using fluxmeters and by the conduction solution method from surface temperature measurements. Numerical predictions are made by solving the Navier-Stokes equations in a full three-dimensional, time-dependent form using the finite-volume method. Convergence is accelerated using a multigrid algorithm and turbulence modeled using a simple mixing length formulation. Notwithstanding systematic differences between the measurements and the computations, the level of agreement can be regarded as promising in view of the acknowledged uncertainties in the experimental data, the limitations of the turbulence model and, perhaps more importantly, the modest grid densities used for the computations.

  10. High temperature solid lubricant materials for heavy duty and advanced heat engines

    SciTech Connect (OSTI)

    DellaCorte, C.; Wood, J.C.

    1994-10-01

    Advanced engine designs incorporate higher mechanical and thermal loading to achieve efficiency improvements. This approach often leads to higher operating temperatures of critical sliding elements (e.g. piston ring/cylinder wall contacts and valve guides) which compromise the use of conventional and even advanced synthetic liquid lubricants. For these applications solid lubricants must be considered. Several novel solid lubricant composites and coatings designated PS/PM200 have been employed to dry and marginally oil lubricated contacts in advanced heat engines. These applications include cylinder kits of heavy duty diesels, and high temperature sterling engines, sidewall seals of rotary engines and various exhaust valve and exhaust component applications. The following paper describes the tribological and thermophysical properties of these tribomaterials and reviews the results of applying them to engine applications. Other potential tribological materials and applications are also discussed with particular emphasis to heavy duty and advanced heat engines.

  11. Precision optical slit for high heat load or ultra high vacuum

    DOE Patents [OSTI]

    Andresen, Nord C. (Hayward, CA); DiGennaro, Richard S. (Albany, CA); Swain, Thomas L. (Richmond, CA)

    1995-01-01

    This invention relates generally to slits used in optics that must be precisely aligned and adjusted. The optical slits of the present invention are useful in x-ray optics, x-ray beam lines, optical systems in which the entrance slit is critical for high wavelength resolution. The invention is particularly useful in ultra high vacuum systems where lubricants are difficult to use and designs which avoid the movement of metal parts against one another are important, such as monochrometers for high wavelength resolution with ultra high vacuum systems. The invention further relates to optical systems in which temperature characteristics of the slit materials is important. The present invention yet additionally relates to precision slits wherein the opposing edges of the slit must be precisely moved relative to a center line between the edges with each edge retaining its parallel orientation with respect to the other edge and/or the center line.

  12. Precision optical slit for high heat load or ultra high vacuum

    DOE Patents [OSTI]

    Andresen, N.C.; DiGennaro, R.S.; Swain, T.L.

    1995-01-24

    This invention relates generally to slits used in optics that must be precisely aligned and adjusted. The optical slits of the present invention are useful in x-ray optics, x-ray beam lines, optical systems in which the entrance slit is critical for high wavelength resolution. The invention is particularly useful in ultra high vacuum systems where lubricants are difficult to use and designs which avoid the movement of metal parts against one another are important, such as monochromators for high wavelength resolution with ultra high vacuum systems. The invention further relates to optical systems in which temperature characteristics of the slit materials is important. The present invention yet additionally relates to precision slits wherein the opposing edges of the slit must be precisely moved relative to a center line between the edges with each edge retaining its parallel orientation with respect to the other edge and/or the center line. 21 figures.

  13. On High-Frequency Sound Generated by Gust-Aerofoil Interaction in Shear Flow

    E-Print Network [OSTI]

    Ayton, Lorna; Peake, Nigel

    2015-02-04

    address for correspondence: L.J.Ayton@damtp.cam.ac.uk Page 1 of 28 2 L. J. Ayton & N. Peake whereby the deployed wing flaps might interact with the engine exhaust flow to produce noise (Mengle et al. 2007; Semiletov et al. 2013). In much of the work... of a large structural element upstream, or by the non-uniform flow entering the aeroengine due to incidence or other installation effects; while in the context of flap- exhaust noise, the bypass/jet exhaust flow is highly sheared. We therefore believe...

  14. Heating and Ionization of the Primordial Intergalactic Medium by High Mass X-ray Binaries

    E-Print Network [OSTI]

    Knevitt, Gillian; Power, Chris; Bolton, James

    2014-01-01

    We investigate the influence of High Mass X-ray Binaries on their high redshift environments. Using a one-dimensional radiative transfer code, we predict the ionization and temperature profiles surrounding a coeval stellar population, composed of main sequence stars and HMXBs, at various times after its formation. We consider both uniform density surroundings, and a cluster embedded in a 10^8 solar mass NFW halo. HMXBs in a constant density environment produce negligible enhanced ionization because of their high-energy SEDs and short lifetimes. In this case, HMXBs only marginally contribute to the local heating rate. For NFW profiles, radiation from main sequence stars cannot prevent the initially ionized volume from recombining since it is unable to penetrate the high density galactic core. However, HMXB photons stall recombinations behind the front, keeping it partially ionized for longer. The increased electron density in these partially ionized regions promotes further cooling, resulting in lower IGM temp...

  15. Nearby-fluids equilibria. II. Zonal flows in a high-, self-organized plasma experiment

    E-Print Network [OSTI]

    Washington at Seattle, University of

    Nearby-fluids equilibria. II. Zonal flows in a high- , self-organized plasma experiment L. C. Steinhauera and H. Y. Guo University of Washington, Redmond Plasma physics Laboratory, Redmond, Washington structure observed in a high- field reversed configuration FRC produced in the translation, confinement

  16. A Proposal for Data Collection: Saturation Flows at Signalized Intersections with high Pedestrian

    E-Print Network [OSTI]

    Bertini, Robert L.

    A Proposal for Data Collection: Saturation Flows at Signalized Intersections with high Pedestrian this estimation including pedestrian traffic, lane width, transit, and traffic composition. Our proposed project and pedestrian volumes at a minimum of three signalized intersections with high pedestrian traffic located

  17. Massively-parallel Spectral Element Algorithm Development for High Speed Flows 

    E-Print Network [OSTI]

    Camp, Joshua Lane

    2013-10-07

    struggle (an example of this being combustor flows). A relatively recent compromise between the stringent requirement of DNS and the reduced accuracy of RANS is large-eddy simulation, or LES. Although many variants exist, a common approach among LES models... million processes with a parallel efficiency of over 60% [10]. Using NEK5000, our group has simulated several gas turbine components using LES and DNS, including a high pressure turbine blade [14], low pressure turbine blade [15], and cold flow combustor...

  18. Numerical simulation of flow distribution for pebble bed high temperature gas cooled reactors 

    E-Print Network [OSTI]

    Yesilyurt, Gokhan

    2004-09-30

    to be investigated. No detailed complete calculations for this kind of reactor to address these local phenomena are available. This work is an attempt to bridge this gap by evaluating this effect. I.2 TURBULENCE MODEL SELECTION The simulation of these local... number of numerical studies on flows around spherical bodies, none of them use the necessary turbulence models that are required to simulate flow where strong separation exists. With the development of high performance computers built for applications...

  19. User's guide of TOUGH2-EGS-MP: A Massively Parallel Simulator with Coupled Geomechanics for Fluid and Heat Flow in Enhanced Geothermal Systems VERSION 1.0

    SciTech Connect (OSTI)

    Xiong, Yi; Fakcharoenphol, Perapon; Wang, Shihao; Winterfeld, Philip H.; Zhang, Keni; Wu, Yu-Shu

    2013-12-01

    TOUGH2-EGS-MP is a parallel numerical simulation program coupling geomechanics with fluid and heat flow in fractured and porous media, and is applicable for simulation of enhanced geothermal systems (EGS). TOUGH2-EGS-MP is based on the TOUGH2-MP code, the massively parallel version of TOUGH2. In TOUGH2-EGS-MP, the fully-coupled flow-geomechanics model is developed from linear elastic theory for thermo-poro-elastic systems and is formulated in terms of mean normal stress as well as pore pressure and temperature. Reservoir rock properties such as porosity and permeability depend on rock deformation, and the relationships between these two, obtained from poro-elasticity theories and empirical correlations, are incorporated into the simulation. This report provides the user with detailed information on the TOUGH2-EGS-MP mathematical model and instructions for using it for Thermal-Hydrological-Mechanical (THM) simulations. The mathematical model includes the fluid and heat flow equations, geomechanical equation, and discretization of those equations. In addition, the parallel aspects of the code, such as domain partitioning and communication between processors, are also included. Although TOUGH2-EGS-MP has the capability for simulating fluid and heat flows coupled with geomechanical effects, it is up to the user to select the specific coupling process, such as THM or only TH, in a simulation. There are several example problems illustrating applications of this program. These example problems are described in detail and their input data are presented. Their results demonstrate that this program can be used for field-scale geothermal reservoir simulation in porous and fractured media with fluid and heat flow coupled with geomechanical effects.

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

    E-Print Network [OSTI]

    Princeton Plasma Physics Laboratory

    magnetic flux expansion and partial detachment of the outer strike point at several D2 injection rates of acceptable divertor plate material erosion rates and heat fluxes to q 10 MW/m2 , a limit imposedDivertor Heat Flux Mitigation in High-Performance H-mode Plasmas in the National Spherical Torus

  1. Alfv6.n Wave Heating with High-Q Eigenmodes* C. F. F. Karney and F. W. Perkins

    E-Print Network [OSTI]

    Karney, Charles

    Alfv6.n Wave Heating with High-Q Eigenmodes* bY C. F. F. Karney and F. W. Perkins Princeton Plasma Conference on Radio Frequency Plasma Heating California Institute of Technology, CA January 11-13, 1978 *Work supported by U.S. Department of Energy (Contract EY-76-C-02-3073) Link: http

  2. Integrated heat pump system

    SciTech Connect (OSTI)

    Reedy, W.R.

    1988-03-01

    An integrated heat pump and hot water system is described that includes: a heat pump having an indoor heat exchanger and an outdoor heat exchanger that are selectively connected to the suction line and the discharge line respectively of a compressor by a flow reversing means, and to each other by a liquid line having an expansion device mounted therein, whereby heating and cooling is provided to an indoor comfort zone by cycling the flow reversing means, a refrigerant to water heat exchanger having a hot water flow circuit in heat transfer relation with a first refrigerant condensing circuit and a second refrigerant evaporating circuit, a connection mounted in the liquid between the indoor heat exchanger and the expansion device, control means for regulating the flow of refrigerant through the refrigerant to water heat exchanger to selectively transfer heat into and out of the hot water flow circuit.

  3. Heat pump system

    DOE Patents [OSTI]

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

    1982-01-01

    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.

  4. Petrophysical analysis of regional-scale thermal properties for improved simulations of geothermal installations and basin-scale heat and fluid flow

    E-Print Network [OSTI]

    Hartmann, Andreas; Clauser, Christoph

    2008-01-01

    Development of geothermal energy and basin-scale simulations of fluid and heat flow both suffer from uncertain physical rock properties at depth. Therefore, building better prognostic models are required. We analysed hydraulic and thermal properties of the major rock types in the Molasse Basin in Southern Germany. On about 400 samples thermal conductivity, density, porosity, and sonic velocity were measured. Here, we propose a three-step procedure with increasing complexity for analysis of the data set: First, univariate descriptive statistics provides a general understanding of the data structure, possibly still with large uncertainty. Examples show that the remaining uncertainty can be as high as 0.8 W/(m K) or as low as 0.1 W/(m K). This depends on the possibility to subdivide the geologic units into data sets that are also petrophysically similar. Then, based on all measurements, cross-plot and quick-look methods are used to gain more insight into petrophysical relationships and to refine the analysis. Be...

  5. Design and Analysis of High-Performance Air-Cooled Heat Exchanger with an Integrated Capillary-Pumped Loop Heat Pipe

    E-Print Network [OSTI]

    McCarthy, Matthew

    We report the design and analysis of a high-power air-cooled heat exchanger capable of dissipating over 1000 W with 33 W of input electrical power and an overall thermal resistance of less than 0.05 K/W. The novelty of the ...

  6. Dealing with big circulation flow, small temperature difference based on verified dynamic model simulations of a hot water district heating system 

    E-Print Network [OSTI]

    Zhong, L.

    2014-01-01

    d design en enclosure ex exchanger f fuel h heater int internal n number of HES o outside r return s supply sp set point sols solar radiation from south side v verify w, w2i water, water in secondary system for each HES z zone ESL... temperatures, solar radiation and wind speed; the heat balance has been regulated based on the average water temperature in the secondary system by adjusting the water mass flow rate (u1) of each HES in the primary system; and the water mass flow rate...

  7. High-frequency asymptotics and 1-D stability of ZND detonations in the small-heat release and high-overdrive limits

    E-Print Network [OSTI]

    Orr, Kent E.

    High-frequency asymptotics and 1-D stability of ZND detonations in the small-heat release and high overdrive limit to a finite, regular perturbation problem, and a careful high-frequency analysis depending uniformly on model parameters. The latter recovers the important result of high-frequency stability

  8. Phase Change Heat Transfer Device for Process Heat Applications

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

    2010-10-01

    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 approx.1300 K) and industrial scale power transport (=50MW), 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 thermal 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) of vapor flow and/or by condensate entrainment. Proper thermosyphon requires analysis of both.

  9. Modeling of Heat Transfer in Rooms in the Modelica Buildings Library

    E-Print Network [OSTI]

    Wetter, Michael

    2013-01-01

    U ) and flow variables (heat flow rate ? mass flow rate m,variables temperature T and heat flow rate Q flow. Then, thesuch as prescribed heat flow rate or temperature. Thus, in

  10. High-Density Plasma Arc Heating Studies of FePt Thin Films

    SciTech Connect (OSTI)

    Cole, Amanda C; Thompson, Gregory; Harrell, J. W.; Weston, James; Ott, Ronald D

    2006-01-01

    The effect of pulsed-thermal-processing with high-density plasma arc heating is discussed for 20 nm thick nanocrystalline FePt thin films. The dependence of the A1 {yields} L1{sub 0} phase transformation on pulsed time and radiant energy of the pulse is quantified through x-ray diffraction and alternating gradient magnetometry. For 100 ms and 250 ms pulse widths, the phase transformation was observed. Higher radiant energy densities resulted in a larger measured coercivity associated with the L1{sub 0} phase.

  11. KEY DESIGN REQUIREMENTS FOR THE HIGH TEMPERATURE GAS-COOLED REACTOR NUCLEAR HEAT SUPPLY SYSTEM

    SciTech Connect (OSTI)

    L.E. Demick

    2010-09-01

    Key requirements that affect the design of the high temperature gas-cooled reactor nuclear heat supply system (HTGR-NHSS) as the NGNP Project progresses through the design, licensing, construction and testing of the first of a kind HTGR based plant are summarized. These requirements derive from pre-conceptual design development completed to-date by HTGR Suppliers, collaboration with potential end users of the HTGR technology to identify energy needs, evaluation of integration of the HTGR technology with industrial processes and recommendations of the NGNP Project Senior Advisory Group.

  12. Three-Dimensional Hydrodynamic Bondi-Hoyle Accretion. V. Specific Heat Ratio 1.01, Nearly Isothermal Flow

    E-Print Network [OSTI]

    M. Ruffert

    1995-10-04

    We investigate the hydrodynamics of three-dimensional classical Bondi-Hoyle accretion. A totally absorbing sphere of different sizes (1, 0.1 and 0.02 accretion radii) moves at different Mach numbers (0.6, 1.4, 3.0 and 10) relative to a homogeneous and slightly perturbed medium, which is taken to be an ideal, nearly isothermal, gas ($\\gamma=1.01$). The hydrodynamics is modeled by the ``Piecewise Parabolic Method'' (PPM). The resolution in the vicinity of the accretor is increased by multiply nesting several $32^3$-zone grids around the sphere, each finer grid being a factor of two smaller in zone size than the next coarser grid. grids. For small Mach numbers (0.6 and~1.4) the flow patterns tend towards a steady state, while in the case of supersonic flow (Mach~3 and~10) and small enough accretors (radius of~0.1 and~0.02 accretion radii), an unstable Mach cone develops, destroying axisymmetry. The shock cones in the supersonic models never clear the surface of the accretors (they are tail shocks, not bow shocks) and the opening angle is smaller (compared to models with larger $\\gamma$) especially for the highly supersonic models. The densities in the shock cone is larger for models with smaller $\\gamma$. The fluctuations of the accretion rates and flow structures are weaker than in the corresponding models with larger $\\gamma$. The hydrodynamic drag of all models with accretor sizes of 0.1~$R_{\\rm A}$ or smaller acts in an accelerating direction, while the gravitational drag is always decelerating and larger than the hydrodynamic drag (thus the net force is decelerating).

  13. The Impact of Refrigerant Charge, Air Flow and Expansion Devices on the Measured Performance of an Air-Source Heat Pump Part I

    SciTech Connect (OSTI)

    Shen, Bo [ORNL

    2011-01-01

    This paper describes extensive tests performed on a 3-ton R-22 split heat pump in heating mode. The tests contain 150 steady-state performance tests, 18 cyclic tests and 18 defrost tests. During the testing work, the refrigerant charge level was varied from 70 % to 130% relative to the nominal value; the outdoor temperature was altered by three levels at 17 F (-8.3 C), 35 F (1.7 C) and 47 F (8.3 C); indoor air flow rates ranged from 60% to 150% of the rated air flow rate; and the expansion device was switched from a fixed-orifice to a thermal expansion value. Detailed performance data from the extensive steady state cyclic and defrost testing performed were presented and compared.

  14. An Evaluation of the Impact of Surface Coatings on the Heat Transfer in High Temperature Ceramic Recuperators 

    E-Print Network [OSTI]

    Guerrero, P. S.; Rebello, W. J.; Federer, J. I.

    1988-01-01

    Engineering ceramics, particularly silicon carbide (SiC), are increasingly being used as materials in high tempera ture recuperators for preheating combus tion air from furnace exhaust gases. As typical flue gases from these furnaces may contain sodium...% in the overall heat transfer coefficient in typical waste heat recovery applications. It was concluded that by combining enhancement techniques on the air side with high emissivity materials on the gas side, one obtains optimal performance in a gas to gas...

  15. Heat Transfer and Pressure Drop Measurement for Square Channels with V-shape Ribs at High Reynolds Numbers 

    E-Print Network [OSTI]

    Alkhamis, Nawaf Yahya

    2010-10-12

    for the degree of MASTER OF SCIENCE August 2009 Major Subject: Mechanical Engineering HEAT TRANSFER AND PRESSURE DROP MEASUREMENT FOR SQUARE CHANNELS WITH V-SHAPE RIBS AT HIGH REYNOLDS NUMBERS A Thesis by NAWAF YAHYA ALKHAMIS... of Department, Dennis O?Neal August 2009 Major Subject: Mechanical Engineering iii ABSTRACT Heat Transfer and Pressure Drop Measurement for Square Channels with V-shape Ribs at High Reynolds Numbers. (August 2009) Nawaf Yahya Alkhamis, B.Sc King...

  16. Introduction to Heat Exchangers

    E-Print Network [OSTI]

    Heller, Barbara

    . Since, the effectiveness can be written in terms of heat capacitance rate [W/K], C, and change in temperature [K], . The heat capacitance rate is defined in terms of mass flow rate [kg/s], , and specific heat: ! ! ! " # = ! ! "# ! ! ! - ! ! ! ! ! ! = ! !! ! ! ! ! = ! ! ! ! ! - ! ! ! ! ! "# ! ! ! - ! ! ! ! ! ! = ! ! ! ! ! - ! ! ! ! ! "# ! ! ! - ! ! ! ! ! Heat%Capacitance%Rate % ! = ! !! ! ! Heat%Capacitance%Rate%[W % ! = ! ! ! ! ! ! ! = ! ! !! ! ! ! max

  17. Transverse flowing liquid Kerr cell for high average power laser Q-switching and for direct modulation of high power laser beams.

    DOE Patents [OSTI]

    Comaskey, Brian J.

    2004-12-07

    A fluid flow concept is applied in an optical apparatus to define a high gain stand-off, fast electro-optical q-switch which is highly impervious to high average power optical loads.

  18. A physically-based heat pump model was connected to an optimization program to form a computer code for use in the design of high-efficiency

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;ABSTRACT A physically-based heat pump model was connected to an optimization program to form a computer code for use in the design of high-efficiency heat pumps. The method used allows efficiency of conventional heat pumps, ten variables were optimized while heating capacity was fixed

  19. Comparative Study of Magnetic Properties of Nanoparticles by High-Frequency Heat Dissipation and Conventional Magnetometry

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

    Malik, V.; Goodwill, J.; Mallapragada, S.; Prozorov, T.; Prozorov, R.

    2014-11-13

    The rate of heating of a water-based colloid of uniformly sized 15 nm magnetic nanoparticles by high-amplitude and high-frequency ac magnetic field induced by the resonating LC circuit (nanoTherics Magnetherm) was measured. The results are analyzed in terms of specific energy absorption rate (SAR). Fitting field amplitude and frequency dependences of SAR to the linear response theory, magnetic moment per particles was extracted. The value of magnetic moment was independently evaluated from dc magnetization measurements (Quantum Design MPMS) of a frozen colloid by fitting field-dependent magnetization to Langevin function. The two methods produced similar results, which are compared to themore »theoretical expectation for this particle size. Additionally, analysis of SAR curves yielded effective relaxation time.« less

  20. Comparative Study of Magnetic Properties of Nanoparticles by High-Frequency Heat Dissipation and Conventional Magnetometry

    SciTech Connect (OSTI)

    Malik, V.; Goodwill, J.; Mallapragada, S.; Prozorov, T.; Prozorov, R.

    2014-11-13

    The rate of heating of a water-based colloid of uniformly sized 15 nm magnetic nanoparticles by high-amplitude and high-frequency ac magnetic field induced by the resonating LC circuit (nanoTherics Magnetherm) was measured. The results are analyzed in terms of specific energy absorption rate (SAR). Fitting field amplitude and frequency dependences of SAR to the linear response theory, magnetic moment per particles was extracted. The value of magnetic moment was independently evaluated from dc magnetization measurements (Quantum Design MPMS) of a frozen colloid by fitting field-dependent magnetization to Langevin function. The two methods produced similar results, which are compared to the theoretical expectation for this particle size. Additionally, analysis of SAR curves yielded effective relaxation time.

  1. High pressure melt ejection and direct containment heating in ice condenser containments

    SciTech Connect (OSTI)

    Pilch, M.; Tarbell, W.W.; Carroll, D.E.; Tills, J.L.

    1986-01-01

    A response of a typical ice condenser containment to a high pressure melt dispersal accident has been studied. While ice beds may be effective in reducing the potential loading caused by direct heating of the containment atmosphere, analyses suggest two other modes of containment failure that have not been previously identified. Calculations with the CONTAIN code indicate that ejected core debris may interact with steam from the primary system, generating sufficient hydrogen to threaten containment integrity. Further, if the debris ejected into the cavity promptly fails the seal table, the dispersed material could enter the in-core instrument room and attack the containment liner. The timing of the failure of the seal table is highly dependent on the characteristics of the debris-to-steel energy transfer.

  2. Heat treatment giving a stable high temperature micro-structure in cast austenitic stainless steel

    DOE Patents [OSTI]

    Anton, Donald L. (Toland, CT); Lemkey, Franklin D. (Windsor, CT)

    1988-01-01

    A novel micro-structure developed in a cast austenitic stainless steel alloy and a heat treatment thereof are disclosed. The alloy is based on a multicomponent Fe-Cr-Mn-Mo-Si-Nb-C system consisting of an austenitic iron solid solution (.gamma.) matrix reinforced by finely dispersed carbide phases and a heat treatment to produce the micro-structure. The heat treatment includes a prebraze heat treatment followed by a three stage braze cycle heat treatment.

  3. Thermofluidics and energetics of a manifold microchannel heat sink for electronics with recovered hot water as working fluid

    E-Print Network [OSTI]

    Daraio, Chiara

    expectation of laminar flow in electronic cooling, high flow rate and high fluid temperatures result in tur- bulent flow conditions in the inlet and outlet manifolds of the heat sink with predominantly laminar flow hot water as working fluid Chander Shekhar Sharma a , Manish K. Tiwari a , Bruno Michel b , Dimos

  4. Microjet array single-phase and flow boiling heat transfer with R134a Eric A. Browne a

    E-Print Network [OSTI]

    Peles, Yoav

    :6 6 Nud 6 128. Boiling experiments were conducted with liquid subcoolings of 10, 20, and 30 °C at jet effective than forced air convection will be required. Single-phase flow and flow boiling in microchannels have been studied [4­10] with a variety of fluids and flow schemes and have been used to cool turbine

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

    SciTech Connect (OSTI)

    Lowe, K.T.

    2005-10-07

    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.

  6. Sequential Thermo-Hydraulic Modeling of Variably Saturated Flow in High-Level Radioactive Waste Repository

    E-Print Network [OSTI]

    Boyer, Edmond

    Sequential Thermo-Hydraulic Modeling of Variably Saturated Flow in High-Level Radioactive Waste-Malabry, France Key words: waste repository, geological disposal, thermo- hydraulic modeling Introduction The most developed a sequential model to predict the coupled thermo-hydraulic processes at a cell-scale radioactive

  7. FLOW OF A FLUID THROUGH A POROUS SOLID DUE TO HIGH PRESSURE GRADIENTS

    E-Print Network [OSTI]

    Bonito, Andrea

    applications involving the flow of fluids through a porous media, like the problems of enhanced oil recovery technical problem where such high pressure differentials are involved is that of extracting unconventional oil deposits such as shale which is becoming ever so important now. In this study, we show

  8. Device and method for electron beam heating of a high density plasma

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high density plasma in a small localized region. A relativistic electron beam generator produces a high voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target plasma is ionized prior to application of the electron beam by means of a laser or other preionization source. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region within the high density plasma target.

  9. Experimental and Analytic Study on the Core Bypass Flow in a Very High Temperature Reactor

    SciTech Connect (OSTI)

    Richard Schultz

    2012-04-01

    Core bypass flow has been one of key issues in the very high temperature reactor (VHTR) design for securing core thermal margins and achieving target temperatures at the core exit. The bypass flow in a prismatic VHTR core occurs through the control element holes and the radial and axial gaps between the graphite blocks for manufacturing and refueling tolerances. These gaps vary with the core life cycles because of the irradiation swelling/shrinkage characteristic of the graphite blocks such as fuel and reflector blocks, which are main components of a core's structure. Thus, the core bypass flow occurs in a complicated multidimensional way. The accurate prediction of this bypass flow and counter-measures to minimize it are thus of major importance in assuring core thermal margins and securing higher core efficiency. Even with this importance, there has not been much effort in quantifying and accurately modeling the effect of the core bypass flow. The main objectives of this project were to generate experimental data for validating the software to be used to calculate the bypass flow in a prismatic VHTR core, validate thermofluid analysis tools and their model improvements, and identify and assess measures for reducing the bypass flow. To achieve these objectives, tasks were defined to (1) design and construct experiments to generate validation data for software analysis tools, (2) determine the experimental conditions and define the measurement requirements and techniques, (3) generate and analyze the experimental data, (4) validate and improve the thermofluid analysis tools, and (5) identify measures to control the bypass flow and assess its performance in the experiment.

  10. Triple integrated heat pump system

    SciTech Connect (OSTI)

    Blackshaw, A.L.; Robinson, G.P. Jr.

    1987-03-03

    A heat pump system is described comprising: a first heat exchange means having first and second refrigerant connections; a second heat exchange means having first and second refrigerant connections; a third heat exchange means having first and second refrigerant connections; a refrigerant pressurizing device having a suction inlet and a high pressure outlet; a reversible refrigerant expansion means for expanding refrigerant from condenser to evaporator pressure connected between the second refrigerant connections on the first and second heat exchange means; an alternate refrigerant expansion means for expanding refrigerant from condenser to evaporator pressure connected to the second refrigerant connection on the third heat exchange means; check valve means connecting the alternate refrigerant expansion means to the common points between the reversible expansion means and each of the first and second heat exchange means so that refrigerant can flow from the alternate expansion means to the first and second heat exchange means but flow of refrigerant from the first and second heat exchange means is prevented; and control valve means.

  11. Measurements of continuous mix evolution in a high energy density shear flow

    SciTech Connect (OSTI)

    Loomis, E. Doss, F.; Flippo, K.; Fincke, J.

    2014-04-15

    We report on the novel integration of streaked radiography into a counter-flowing High Energy Density (HED) shear environment that continually measures a growing mix layer of Al separating two low-density CH foams. Measurements of the mix width allow us to validate compressible turbulence models and with streaked imaging, make this possible with a minimal number of experiments on large laser facilities. In this paper, we describe how the HED counter-flowing shear layer is created and diagnosed with streaked radiography. We then compare the streaked data to previous two-dimensional, single frame radiography and radiation hydrodynamic simulations of the experiment with inline compressible turbulent mix models.

  12. Method and apparatus for optical Doppler tomographic imaging of fluid flow velocity in highly scattering media

    DOE Patents [OSTI]

    Nelson, John Stuart (Laguna Niguel, CA); Milner, Thomas Edward (Irvine, CA); Chen, Zhongping (Irvine, CA)

    1999-01-01

    Optical Doppler tomography permits imaging of fluid flow velocity in highly scattering media. The tomography system combines Doppler velocimetry with high spatial resolution of partially coherent optical interferometry to measure fluid flow velocity at discrete spatial locations. Noninvasive in vivo imaging of blood flow dynamics and tissue structures with high spatial resolutions of the order of 2 to 10 microns is achieved in biological systems. The backscattered interference signals derived from the interferometer may be analyzed either through power spectrum determination to obtain the position and velocity of each particle in the fluid flow sample at each pixel, or the interference spectral density may be analyzed at each frequency in the spectrum to obtain the positions and velocities of the particles in a cross-section to which the interference spectral density corresponds. The realized resolutions of optical Doppler tomography allows noninvasive in vivo imaging of both blood microcirculation and tissue structure surrounding the vessel which has significance for biomedical research and clinical applications.

  13. Control of a high Reynolds number Mach 0.9 heated jet using plasma actuators

    SciTech Connect (OSTI)

    Kearney-Fischer, M.; Kim, J.-H.; Samimy, M.

    2009-09-15

    The results of particle image velocimetry (PIV) measurements in a high subsonic, heated, jet forced using localized arc filament plasma actuators (LAFPAs) show that LAFPAs can consistently produce significant mixing enhancement over a wide range of temperatures. These actuators have been used successfully in high Reynolds number, high-speed unheated jets. The facility consists of an axisymmetric jet with different nozzle blocks of exit diameter of 2.54 cm and variable jet temperature in an anechoic chamber. The focus of this paper is on a high subsonic (M{sub j}=0.9) jet. Twelve experiments with various forcing azimuthal modes (m=0, 1, and {+-}1) and temperatures (T{sub o}/T{sub a}=1.0, 1.4, and 2.0) at a fixed forcing Strouhal number (St{sub DF}=0.3) have been conducted and PIV results compared with the baseline results to characterize the effectiveness of LAFPAs for mixing enhancement. Centerline velocity and turbulent kinetic energy as well as jet width are used for determining the LAFPAs' effectiveness. The characteristics of large-scale structures are analyzed through the use of Galilean streamlines and swirling strength. Across the range of temperatures collected, the effectiveness of LAFPAs improves as temperature increases. Possible reasons for the increase in effectiveness are discussed.

  14. An Experimental Study of Upward and Downward Flow of Supercritical Carbon Dioxide in a Straight Pipe Heat Exchanger with Constant Wall Heat Flux 

    E-Print Network [OSTI]

    Umrigar, Eric Dara

    2014-05-01

    . The HPLC pump had a maximum flow rate of 24 mL/min. Typically, this pump filled the system in about 30 minutes to one hour. A Micropump magnetic gear pump powered by a 0.5 hp Baldor-Reliance electric motor was used to circulate the fluid throughout...

  15. Power flow tracing in a simplified highly renewable European electricity network

    E-Print Network [OSTI]

    Tranberg, Bo; Rodriguez, Rolando A; Andresen, Gorm B; Schäfer, Mirko; Greiner, Martin

    2015-01-01

    The increasing transmission capacity needs in a future energy system raise the question how associated costs should be allocated to the users of a strengthened power grid. In contrast to straightforward oversimplified methods, a flow tracing based approach provides a fair and consistent nodal usage and thus cost assignment of transmission investments. This technique follows the power flow through the network and assigns the link capacity usage to the respective sources or sinks using a diffusion-like process, thus taking into account the underlying network structure and injection pattern. As a showcase, we apply power flow tracing to a simplified model of the European electricity grid with a high share of renewable wind and solar power generation, based on long-term weather and load data with an hourly temporal resolution.

  16. In situ high P-T Raman spectroscopy and laser heating of carbon dioxide Mario Santoro,a)

    E-Print Network [OSTI]

    Lin, Jung-Fu "Afu"

    In situ high P-T Raman spectroscopy and laser heating of carbon dioxide Mario Santoro,a) Jung interpretation of the high P-T phase diagram of carbon dioxide. Furthermore, our approach opens a new way energy of the electrons. Solid-solid phase transitions thus occur to minimize the overall energy

  17. Facility for high heat flux testing of irradiated fusion materials and components using infrared plasma arc lamps

    SciTech Connect (OSTI)

    Sabau, Adrian S; Ohriner, Evan Keith; Kiggans, Jim; Harper, David C; Snead, Lance Lewis; Schaich, Charles Ross

    2014-01-01

    A new high-heat flux testing facility using water-wall stabilized high-power high-pressure argon Plasma Arc Lamps (PALs) has been developed for fusion applications. It can handle irradiated plasma facing component materials and mock-up divertor components. Two PALs currently available at ORNL can provide maximum incident heat fluxes of 4.2 and 27 MW/m2 over a heated area of 9x12 and 1x10 cm2, respectively, which are fusion-prototypical steady state heat flux conditions. The facility will be described and the main differences between the photon-based high-heat flux testing facilities, such as PALs, and the e-beam and particle beam facilities more commonly used for fusion HHF testing are discussed. The components of the test chamber were designed to accommodate radiation safety and materials compatibility requirements posed by high-temperature exposure of low levels irradiated tungsten articles. Issues related to the operation and temperature measurements during testing are presented and discussed.

  18. Urban Physiology: City Ants Possess High Heat Tolerance Michael J. Angilletta Jr1

    E-Print Network [OSTI]

    Angilletta, Michael

    on a global scale, leading to urban heat islands as much as 12uC hotter than their surroundings. Optimality, and the unusual pattern of convection [1]. Urban heat islands--increased temperatures within urban areas-- scale [6­8]. Urban heat islands should not only concern ecologists who wish to manage urban populations

  19. Dual source heat pump

    DOE Patents [OSTI]

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

    1982-01-01

    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.

  20. Laser Doppler field sensor for high resolution flow velocity imaging without camera

    SciTech Connect (OSTI)

    Voigt, Andreas; Bayer, Christian; Shirai, Katsuaki; Buettner, Lars; Czarske, Juergen

    2008-09-20

    In this paper we present a laser sensor for highly spatially resolved flow imaging without using a camera. The sensor is an extension of the principle of laser Doppler anemometry (LDA). Instead of a parallel fringe system, diverging and converging fringes are employed. This method facilitates the determination of the tracer particle position within the measurement volume and leads to an increased spatial and velocity resolution compared to conventional LDA. Using a total number of four fringe systems the flow is resolved in two spatial dimensions and the orthogonal velocity component. Since no camera is used, the resolution of the sensor is not influenced by pixel size effects. A spatial resolution of 4 {mu}m in the x direction and 16 {mu}m in the y direction and a relative velocity resolution of 1x10{sup -3} have been demonstrated up to now. As a first application we present the velocity measurement of an injection nozzle flow. The sensor is also highly suitable for applications in nano- and microfluidics, e.g., for the measurement of flow rates.

  1. Process for oil shale retorting using gravity-driven solids flow and solid-solid heat exchange

    DOE Patents [OSTI]

    Lewis, A.E.; Braun, R.L.; Mallon, R.G.; Walton, O.R.

    1983-09-21

    A cascading bed retorting process and apparatus are disclosed in which cold raw crushed shale enters at the middle of a retort column into a mixer stage where it is rapidly mixed with hot recycled shale and thereby heated to pyrolysis temperature. The heated mixture then passes through a pyrolyzer stage where it resides for a sufficient time for complete pyrolysis to occur. The spent shale from the pyrolyzer is recirculated through a burner stage where the residual char is burned to heat the shale which then enters the mixer stage.

  2. Process for oil shale retorting using gravity-driven solids flow and solid-solid heat exchange

    DOE Patents [OSTI]

    Lewis, Arthur E. (Los Altos, CA); Braun, Robert L. (Livermore, CA); Mallon, Richard G. (Livermore, CA); Walton, Otis R. (Livermore, CA)

    1986-01-01

    A cascading bed retorting process and apparatus in which cold raw crushed shale enters at the middle of a retort column into a mixer stage where it is rapidly mixed with hot recycled shale and thereby heated to pyrolysis temperature. The heated mixture then passes through a pyrolyzer stage where it resides for a sufficient time for complete pyrolysis to occur. The spent shale from the pyrolyzer is recirculated through a burner stage where the residual char is burned to heat the shale which then enters the mixer stage.

  3. Fluidized bed heat treating system

    DOE Patents [OSTI]

    Ripley, Edward B; Pfennigwerth, Glenn L

    2014-05-06

    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.

  4. High pressure counterflow CHF.

    E-Print Network [OSTI]

    Walkush, Joseph Patrick

    1975-01-01

    This is a report of the experimental results of a program in countercurrent flow critical heat flux. These experiments were performed with Freon 113 at 200 psia in order to model a high pressure water system. An internally ...

  5. A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat Flow Simulations

    E-Print Network [OSTI]

    Elmroth, Erik

    of Energy's civilian nuclear waste management for the evaluation of the Yucca Mountain site as a repository groundwater flow related problems such as nuclear waste isolation, environmental remediation, and geothermal 6 blocks in a Yucca Mountain nuclear waste site study. Keywords. Ground water flow, grid

  6. Study of instabilities and quasi-two-dimensional turbulence in volumetrically heated magnetohydrodynamic flows in a vertical rectangular duct

    E-Print Network [OSTI]

    Abdou, Mohamed

    magnetohydrodynamic flows in a vertical rectangular duct N. Vetcha, S. Smolentsev, M. Abdou, and R. Moreau Citation in a vertical rectangular duct N. Vetcha,1 S. Smolentsev,1,a) M. Abdou,1 and R. Moreau2 1 Mechanical 2013; published online 15 February 2013) We consider magnetohydrodynamic (MHD) rectangular duct flows

  7. A Parallel Implementation of the TOUGH2 Software Package for Large Scale Multiphase Fluid and Heat Flow Simulations

    E-Print Network [OSTI]

    Elmroth, Erik

    with ¢¡¤£¦¥§ ¨¡© blocks in a Yucca Mountain nuclear waste site study. Keywords. Ground water flow, grid partitioning management for the evaluation of the Yucca Mountain site as a repository for nuclear wastes. In this context of developing a 3D flow model of the Yucca Mountain site, involving computational grids of to blocks

  8. Influences of peripherally-cut twisted tape insert on heat transfer and thermal performance characteristics in laminar and turbulent tube flows

    SciTech Connect (OSTI)

    Eiamsa-ard, Smith [Department of Mechanical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Seemawute, Panida [Department of Civil Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Wongcharee, Khwanchit [Department of Chemical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand)

    2010-09-15

    Effects of peripherally-cut twisted tape insert on heat transfer, friction loss and thermal performance factor characteristics in a round tube were investigated. Nine different peripherally-cut twisted tapes with constant twist ratio (y/W = 3.0) and different three tape depth ratios (DR = d/W = 0.11, 0.22 and 0.33), each with three different tape width ratios (WR = w/W = 0.11, 0.22 and 0.33) were tested. Besides, one typical twisted tape was also tested for comparison. The measurement of heat transfer rate was conducted under uniform heat flux condition while that of friction factor was performed under isothermal condition. Tests were performed with Reynolds number in a range from 1000 to 20,000, using water as a working fluid. The experimental results revealed that both heat transfer rate and friction factor in the tube equipped with the peripherally-cut twisted tapes were significantly higher than those in the tube fitted with the typical twisted tape and plain tube, especially in the laminar flow regime. The higher turbulence intensity of fluid in the vicinity of the tube wall generated by the peripherally-cut twisted tape compared to that induced by the typical twisted tape is referred as the main reason for achieved results. The obtained results also demonstrated that as the depth ratio increased and width ratio decreased, the heat transfer enhancement increased. Over the range investigated, the peripherally-cut twisted tape enhanced heat transfer rates in term of Nusselt numbers up to 2.6 times (turbulent regime) and 12.8 times (laminar regime) of that in the plain tube. These corresponded to the maximum performance factors of 1.29 (turbulent regime) and 4.88 (laminar regime). (author)

  9. Micro Catalytic Combustor with Pd/Nano-porous Alumina for High-Temperature Application

    E-Print Network [OSTI]

    Kasagi, Nobuhide

    . A heat exchanger with a temperature efficiency of 0.78 is assumed for heat recirculation. Thus as high as 850 o C and extremely high heat generation density of 2-5x108 W/m3 has been achieved been made for radial-flow-type combustors using Fluent 6 (Fluent Inc.). Figure 1 shows a radial-flow-type

  10. Laminar Flow Forced Convection Heat Transfer Behavior of Phase Change Material Fluid in Straight and Staggered Pin Microchannels 

    E-Print Network [OSTI]

    Kondle, Satyanarayana

    2011-10-21

    the geometry shape, solid and fluid materials used, and surface roughness, among others. Many configurations of microchannels have been studied with various materials and compared for their effectiveness in heat removal. However, there is little research done...

  11. 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. These refractory devices take advantage of high temperature operation with large delta-Ts to effectively handle helium flow loop at Sandia National Laboratories. The module survived a maximum absorbed heat flux of 34

  12. Effects of high temperature and flow blockage on the reflood behavior of a 4-rod bundle. Final report. [PWR

    SciTech Connect (OSTI)

    Drucker, M.; Dhir, V.K.

    1981-11-01

    It is usual in reactor safety analysis to assume that blocking or deforming the reactor core decreases the heat removal. This simplistic approach may not only penalize reactor power, but must be investigated experimentally to determine the real extent, if any. The experiments reported here examine quenching and heat removal in a blocked four-rod bundle. The local heat transfer in the blockage region is enhanced, despite the flow diversion away from the blockage. Additionally, data and correlations are given which compare the quenching rate of steel pins (typical of experiments) with Zircaloy (typical of reactor cladding). The Zircaloy bundle quenches faster when correlated on a local basis because of its smaller heat capacity. Additional work is under way to explain and correlate the intriguing results in more detail.

  13. Analysis of instability inception in high-speed multistage axial-flow compressors

    SciTech Connect (OSTI)

    Hendricks, G.J.; Sabnis, J.S.; Feulner, M.R.

    1997-10-01

    A nonlinear, two-dimensional, compressible dynamic model has been developed to study rotating stall/surge inception and development in high-speed, multistage, axial flow compressors. The flow dynamics are represented by the unsteady Euler equations, solved in each interblade row gap and inlet and exit ducts as two-dimensional domains, and in each blade passage as a one-dimensional domain. The resulting equations are solved on a computational grid. The boundary conditions between domains are represented by ideal turning coupled with empirical loss and deviation correlations. Results are presented comparing model simulations to instability inception data of an eleven stage, high-pressure-ratio compressor operating at both part and full power, and the results analyzed in the context of a linear modal analysis.

  14. Characterization of the reactive flow field dynamics in a gas turbine injector using high frequency PIV

    E-Print Network [OSTI]

    Barbosa, Séverine; Ducruix, Sébastien

    2008-01-01

    The present work details the analysis of the aerodynamics of an experimental swirl stabilized burner representative of gas turbine combustors. This analysis is carried out using High Frequency PIV (HFPIV) measurements in a reactive situation. While this information is usually available at a rather low rate, temporally resolved PIV measurements are necessary to better understand highly turbulent swirled flows, which are unsteady by nature. Thanks to recent technical improvements, a PIV system working at 12 kHz has been developed to study this experimental combustor flow field. Statistical quantities of the burner are first obtained and analyzed, and the measurement quality is checked, then a temporal analysis of the velocity field is carried out, indicating that large coherent structures periodically appear in the combustion chamber. The frequency of these structures is very close to the quarter wave mode of the chamber, giving a possible explanation for combustion instability coupling.

  15. Vitrification of high level nuclear waste inside ambient temperature disposal containers using inductive heating: The SMILE system

    SciTech Connect (OSTI)

    Powell, J.; Reich, M.; Barletta, R.

    1996-03-01

    A new approach, termed SMILE (Small Module Inductively Loaded Energy), for the vitrification of high level nuclear wastes (HLW) is described. Present vitrification systems liquefy the HLW solids and associated frit material in large high temperature melters. The molten mix is then poured into small ({approximately}1 m{sup 3}) disposal canisters, where it solidifies and cools. SMILE eliminates the separate, large high temperature melter. Instead, the BLW solids and frit melt inside the final disposal containers, using inductive heating. The contents then solidify and cool in place. The SMILE modules and the inductive heating process are designed so that the outer stainless can of the module remains at near ambient temperature during the process cycle. Module dimensions are similar to those of present disposal containers. The can is thermally insulated from the high temperature inner container by a thin layer of refractory alumina firebricks. The inner container is a graphite crucible lined with a dense alumina refractory that holds the HLW and fiit materials. After the SMILE module is loaded with a slurry of HLW and frit solids, an external multi-turn coil is energized with 30-cycle AC current. The enclosing external coil is the primary of a power transformer, with the graphite crucible acting as a single turn ``secondary.`` The induced current in the ``secondary`` heats the graphite, which in turn heats the HLW and frit materials. The first stage of the heating process is carried out at an intermediate temperature to drive off remnant liquid water and water of hydration, which takes about 1 day. The small fill/vent tube to the module is then sealed off and the interior temperature raised to the vitrification range, i.e., {approximately}1200C. Liquefaction is complete after approximately 1 day. The inductive heating then ceases and the module slowly loses heat to the environment, allowing the molten material to solidify and cool down to ambient temperature.

  16. Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Ultra-High Energy Efficient Research Homes

    SciTech Connect (OSTI)

    Im, Piljae; Hughes, Patrick; Liu, Xiaobing

    2012-01-01

    The more widespread use of Ground Source Heat Pump (GSHP) systems has been hindered by their high first cost, which is mainly driven by the cost of the drilling and excavation for installation of ground heat exchangers (GHXs). A new foundation heat exchanger (FHX) technology was proposed to reduce first cost by placing the heat exchanger into the excavations made during the course of construction (e.g., the overcut for the basement and/or foundation and run-outs for water supply and the septic field). Since they reduce or eliminate the need for additional drilling or excavation, foundation heat exchangers have the potential to significantly reduce or eliminate the first cost premium associated with GSHPs. Since December 2009, this FHX technology has been demonstrated in two ultra-high energy efficient new research houses in the Tennessee Valley, and the performance data has been closely monitored as well. This paper introduces the FHX technology with the design, construction and demonstration of the FHX and presents performance monitoring results of the FHX after one year of monitoring. The performance monitoring includes hourly maximum and minimum entering water temperature (EWT) in the FHX compared with the typical design range, temperature difference (i.e., T) across the FHX, and hourly heat transfer rate to/from the surrounding soil.

  17. Coal plasticity at high heating rates and temperatures. Final technical progress report

    SciTech Connect (OSTI)

    Gerjarusak, S.; Peters, W.A.; Howard, J.B.

    1995-05-01

    Plastic coals are important feedstocks in coke manufacture, coal liquefaction, gasification, and combustion. During these processes, the thermoplastic behavior of these coals is also important since it may contribute to desirable or undesirable characteristics. For example, during liquefaction, the plastic behavior is desired since it leads to liquid-liquid reactions which are faster than solid-liquid reactions. During gasification, the elastic behavior is undesired since it leads to caking and agglomeration of coal particles which result in bed bogging in fixed or fluidized bed gasifiers. The plastic behavior of different coals was studied using a fast-response plastometer. A modified plastometer was used to measure the torque required to turn at constant angular speed a cone-shaped disk embedded in a thin layer of coal. The coal particles were packed between two metal plates which are heated electrically. Heating rates, final temperatures, pressures, and durations of experiment ranged from 200--800 K/s, 700--1300 K, vacuum-50 atm helium, and 0--40 s, respectively. The apparent viscosity of the molten coal was calculated from the measured torque using the governing equation of the cone-and-plate viscometer. Using a concentrated suspension model, the molten coal`s apparent viscosity was related to the quantity of the liquid metaplast present during pyrolysis. Seven coals from Argonne National Laboratory Premium Coal Sample Bank were studied. Five bituminous coals, from high-volatile to low-volatile bituminous, were found to have very good plastic behavior. Coal type strongly affects the magnitude and duration of plasticity. Hvb coals were most plastic. Mvb and lvb coals, though the maximum plasticity and plastic period were less. Low rank coals such as subbituminous and lignite did not exhibit any plasticity in the present studies. Coal plasticity is moderately well correlated with simple indices of coal type such as the elemental C,O, and H contents.

  18. Parallel-plate heat pipe apparatus having a shaped wick structure

    DOE Patents [OSTI]

    Rightley, Michael J.; Adkins, Douglas R.; Mulhall, James J.; Robino, Charles V.; Reece, Mark; Smith, Paul M.; Tigges, Chris P.

    2004-12-07

    A parallel-plate heat pipe is disclosed that utilizes a plurality of evaporator regions at locations where heat sources (e.g. semiconductor chips) are to be provided. A plurality of curvilinear capillary grooves are formed on one or both major inner surfaces of the heat pipe to provide an independent flow of a liquid working fluid to the evaporator regions to optimize heat removal from different-size heat sources and to mitigate the possibility of heat-source shadowing. The parallel-plate heat pipe has applications for heat removal from high-density microelectronics and laptop computers.

  19. High Bandwidth Micro-Actuators for Active Flow John T Solomon1

    E-Print Network [OSTI]

    of the mean flow. The potential of Hartmann tube or modified Hartmann resonators for active flow control has

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

    SciTech Connect (OSTI)

    Holcomb, G.R.

    2008-04-01

    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.