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Note: This page contains sample records for the topic "heat transfer fluid" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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1

MOLTEN SALT HEAT TRANSFER FLUID  

thermal energy storage tanks Sandia has developed a heat transfer fluid (HTF) for use at elevated temperatures that has a lower freezing point

2

Heat Transfer Fluids Containing Nanoparticles  

commercial and industrial heat-transfer applications. ... Refrigeration and other cooling systems Nuclear reactors Aerospace Defense Grinding and ...

3

Heat Transfer in Complex Fluids  

SciTech Connect

Amongst the most important constitutive relations in Mechanics, when characterizing the behavior of complex materials, one can identify the stress tensor T, the heat flux vector q (related to heat conduction) and the radiant heating (related to the radiation term in the energy equation). Of course, the expression 'complex materials' is not new. In fact, at least since the publication of the paper by Rivlin & Ericksen (1955), who discussed fluids of complexity (Truesdell & Noll, 1992), to the recently published books (Deshpande et al., 2010), the term complex fluids refers in general to fluid-like materials whose response, namely the stress tensor, is 'non-linear' in some fashion. This non-linearity can manifest itself in variety of forms such as memory effects, yield stress, creep or relaxation, normal-stress differences, etc. The emphasis in this chapter, while focusing on the constitutive modeling of complex fluids, is on granular materials (such as coal) and non-linear fluids (such as coal-slurries). One of the main areas of interest in energy related processes, such as power plants, atomization, alternative fuels, etc., is the use of slurries, specifically coal-water or coal-oil slurries, as the primary fuel. Some studies indicate that the viscosity of coal-water mixtures depends not only on the volume fraction of solids, and the mean size and the size distribution of the coal, but also on the shear rate, since the slurry behaves as shear-rate dependent fluid. There are also studies which indicate that preheating the fuel results in better performance, and as a result of such heating, the viscosity changes. Constitutive modeling of these non-linear fluids, commonly referred to as non-Newtonian fluids, has received much attention. Most of the naturally occurring and synthetic fluids are non-linear fluids, for example, polymer melts, suspensions, blood, coal-water slurries, drilling fluids, mud, etc. It should be noted that sometimes these fluids show Newtonian (linear) behavior for a given range of parameters or geometries; there are many empirical or semi-empirical constitutive equations suggested for these fluids. There have also been many non-linear constitutive relations which have been derived based on the techniques of continuum mechanics. The non-linearities oftentimes appear due to higher gradient terms or time derivatives. When thermal and or chemical effects are also important, the (coupled) momentum and energy equations can give rise to a variety of interesting problems, such as instability, for example the phenomenon of double-diffusive convection in a fluid layer. In Conclusion, we have studied the flow of a compressible (density gradient type) non-linear fluid down an inclined plane, subject to radiation boundary condition. The heat transfer is also considered where a source term, similar to the Arrhenius type reaction, is included. The non-dimensional forms of the equations are solved numerically and the competing effects of conduction, dissipation, heat generation and radiation are discussed. It is observed that the velocity increases rapidly in the region near the inclined surface and is slower in the region near the free surface. Since R{sub 7} is a measure of the heat generation due to chemical reaction, when the reaction is frozen (R{sub 7}=0.0) the temperature distributions would depend only on R{sub 1}, and R{sub 2}, representing the effects of the pressure force developed in the material due to the distribution, R{sub 3} and R{sub 4} viscous dissipation, R{sub 5} the normal stress coefficient, R{sub 6} the measure of the emissivity of the particles to the thermal conductivity, etc. When the flow is not frozen (RP{sub 7} > 0) the temperature inside the flow domain is much higher than those at the inclined and free surfaces. As a result, heat is transferred away from the flow toward both the inclined surface and the free surface with a rate that increases as R{sub 7} increases. For a given temperature, an increase in {zeta} implies that the activation energy is smaller and thus, the reaction ra

Mehrdad Massoudi

2012-01-01T23:59:59.000Z

4

"Nanotechnology Enabled Advanced Industrial Heat Transfer Fluids"  

DOE Green Energy (OSTI)

ABSTRACT Nanotechnology Enabled Advanced industrial Heat Transfer Fluids” Improving the efficiency of Industrial Heat Exchangers offers a great opportunity to improve overall process efficiencies in diverse industries such as pharmaceutical, materials manufacturing and food processing. The higher efficiencies can come in part from improved heat transfer during both cooling and heating of the material being processed. Additionally, there is great interest in enhancing the performance and reducing the weight of heat exchangers used in automotives in order to increase fuel efficiency. The goal of the Phase I program was to develop nanoparticle containing heat transfer fluids (e.g., antifreeze, water, silicone and hydrocarbon-based oils) that are used in transportation and in the chemical industry for heating, cooling and recovering waste heat. Much work has been done to date at investigating the potential use of nanoparticle-enhanced thermal fluids to improve heat transfer in heat exchangers. In most cases the effect in a commercial heat transfer fluid has been marginal at best. In the Phase I work, we demonstrated that the thermal conductivity, and hence heat transfer, of a fluid containing nanoparticles can be dramatically increased when subjected to an external influence. The increase in thermal conductivity was significantly larger than what is predicted by commonly used thermal models for two-phase materials. Additionally, the surface of the nanoparticles was engineered so as to have a minimal influence on the viscosity of the fluid. As a result, a nanoparticle-laden fluid was successfully developed that can lead to enhanced heat transfer in both industrial and automotive heat exchangers

Dr. Ganesh Skandan; Dr. Amit Singhal; Mr. Kenneth Eberts; Mr. Damian Sobrevilla; Prof. Jerry Shan; Stephen Tse; Toby Rossmann

2008-06-12T23:59:59.000Z

5

Advanced Heat Transfer and Thermal Storage Fluids  

DOE Green Energy (OSTI)

The design of the next generation solar parabolic trough systems for power production will require the development of new thermal energy storage options with improved economics or operational characteristics. Current heat-transfer fluids such as VP-1?, which consists of a eutectic mixture of biphenyl and diphenyl oxide, allow a maximum operating temperature of ca. 300 C, a limit above which the vapor pressure would become too high and would require pressure-rated tanks. The use of VP-1? also suffers from a freezing point around 13 C that requires heating during cold periods. One of the goals for future trough systems is the use of heat-transfer fluids that can act as thermal storage media and that allow operating temperatures around 425 C combined with lower limits around 0 C. This paper presents an outline of our latest approach toward the development of such thermal storage fluids.

Moens, L.; Blake, D.

2005-01-01T23:59:59.000Z

6

SPECIAL HEAT TRANSFER PHENOMENA FOR SUPERCRITICAL FLUIDS  

SciTech Connect

Present-day knowledge concerning the molecular structure of supercritical fluids is briefly reviewed. It is shown that liquid-like and gas- like phases may coexist at supercritical pressures, although they may not be in equllibrium with each other. it is postulated that on the basis of the coexistence of these two phases a "boiling-like" phenomenon may provide the mechanism of heat transfer to supercritical fluids at high heat fluxes and certain other conditions. An unusual mode of heat transfer was actually observed at supercritical pressures during tests which produced the high heat fluxes and other conditions under which such "boiling" would be expected. The tests and the various conditions are briefly described. An emission of high-frequeney, high- intensity sounds usually accompanied these tests. It is shown that similar screaming sounds were heard during boiling at subcritical pressures, giving further support to the hypothesis that "boiling" may occur at supercritical pressures. A seeond possible explanation for the unusual mode of heat transfer is based on boundarylayer stability considerations. At high heat fluxes large density differences exist between the bulk of the fluid and the fluid in the boundary layer near the wall. A breakdown of the boundary layer may be caused by the build-up of ripples between its low-density fluid and the high-density bulk fluid, in a manner quite similar to the breaking of ocean waves at high wind velocities. It is pointed out that the density variation of supercritical fluide may be used to advantage by certrifuging boundary layers. (auth)

Goldmann, K.

1956-01-01T23:59:59.000Z

7

Molten Salt Heat Transfer Fluid (HTF) - Energy Innovation Portal  

Solar Thermal Industrial Technologies Energy Storage Molten Salt Heat Transfer Fluid (HTF) Sandia National Laboratories. Contact SNL About This ...

8

Thermal Storage and Advanced Heat Transfer Fluids (Fact Sheet...  

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

Thermophysical Properties In our Thermal Storage Materials Laboratory, we use a variety of instruments to measure the thermophysical properties of heat transfer fluids and storage...

9

Handbook of thermodynamics, heat transfer and fluid flow  

E-Print Network (OSTI)

9 Nov 2010 ... Handbook of thermodynamics, heat transfer and fluid flow | JUNE 1992 | 3 Volume | U.S. Department of Energy FSC-6910 Washington, D.C. ...

10

Engineering Fundamentals - Heat Transfer & Fluid Flow, Version 6.0  

Science Conference Proceedings (OSTI)

The Heat Transfer and Fluid Flow module covers basic terms and concepts of heat transfer and fluid flow and discusses their applications in nuclear power plants. This course will help new engineers understand how their work might impact and/or be ...

2013-01-17T23:59:59.000Z

11

Heat Transfer and Fluid Mechanics - Nuclear Engineering Division (Argonne)  

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

Engineering Computation Engineering Computation and Design > Heat Transfer and Fluid Mechanics Capabilities Engineering Computation and Design Engineering and Structural Mechanics Systems/Component Design, Engineering and Drafting Heat Transfer and Fluid Mechanics Overview Thermal Hydraulic Optimization of Nuclear Systems Underhood Thermal Management Combustion Simulations Advanced Model and Methodology Development Multi-physics Reactor Performance and Safety Simulations Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Heat Transfer and Fluid Mechanics Bookmark and Share Engineering Simulation Capabilities at Argonne Nuclear Engineering Division The Engineering Simulation section specializes in the development and

12

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

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

Heat Transfer Fluids for Solar Thermal Power Generation UCLA, UCB, Yale Award Number: DE-EE0005941 | January 9, 2013 | Sungtaek Ju 1.1 Thermochemistry modeling Identified promising...

13

Heat Transfer Fluids for Solar Water Heating Systems | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Heat Transfer Fluids for Solar Water Heating Systems Heat Transfer Fluids for Solar Water Heating Systems Heat Transfer Fluids for Solar Water Heating Systems May 16, 2013 - 3:02pm Addthis Illustration of a solar water heater. Illustration of a solar water heater. Heat-transfer fluids carry heat through solar collectors and a heat exchanger to the heat storage tanks in solar water heating systems. When selecting a heat-transfer fluid, you and your solar heating contractor should consider the following criteria: Coefficient of expansion - the fractional change in length (or sometimes in volume, when specified) of a material for a unit change in temperature Viscosity - resistance of a liquid to sheer forces (and hence to flow) Thermal capacity - the ability of matter to store heat Freezing point - the temperature below which a liquid turns into a

14

Advanced Model and Methodology Development [Heat Transfer and Fluid  

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

Advanced Model and Advanced Model and Methodology Development Capabilities Engineering Computation and Design Engineering and Structural Mechanics Systems/Component Design, Engineering and Drafting Heat Transfer and Fluid Mechanics Overview Thermal Hydraulic Optimization of Nuclear Systems Underhood Thermal Management Combustion Simulations Advanced Model and Methodology Development Multi-physics Reactor Performance and Safety Simulations Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Heat Transfer and Fluid Mechanics Bookmark and Share Advanced Model and Methodology Development Electrorefiner Model for Treatment of Spent Nuclear Fuel Electrorefiner Model for Treatment of Spent Nuclear Fuel. Click on image to

15

Thermal Hydraulic Optimization of Nuclear Systems [Heat Transfer and Fluid  

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

Thermal Hydraulic Thermal Hydraulic Optimization of Nuclear Systems Capabilities Engineering Computation and Design Engineering and Structural Mechanics Systems/Component Design, Engineering and Drafting Heat Transfer and Fluid Mechanics Overview Thermal Hydraulic Optimization of Nuclear Systems Underhood Thermal Management Combustion Simulations Advanced Model and Methodology Development Multi-physics Reactor Performance and Safety Simulations Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Heat Transfer and Fluid Mechanics Bookmark and Share Thermal Hydraulic Optimization of Nuclear Systems Accelerator Driven Test Facility Target Accelerator Driven Test Facility Target. Click on image to view larger

16

Underhood Thermal Management [Heat Transfer and Fluid Mechanics] - Nuclear  

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

Underhood Thermal Underhood Thermal Management Capabilities Engineering Computation and Design Engineering and Structural Mechanics Systems/Component Design, Engineering and Drafting Heat Transfer and Fluid Mechanics Overview Thermal Hydraulic Optimization of Nuclear Systems Underhood Thermal Management Combustion Simulations Advanced Model and Methodology Development Multi-physics Reactor Performance and Safety Simulations Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Heat Transfer and Fluid Mechanics Bookmark and Share Underhood Thermal Management Hybrid Vehicle Underhood Thermal Analysis Hybrid Vehicle Underhood Thermal Analysis. Click on image to view larger image. In addition to nuclear system applications, the section applies its

17

Optical techniques for fluid flow and heat transfer  

Science Conference Proceedings (OSTI)

A review is presented of optical measuring techniques employed in momentum heat and mass transfer studies. A classification is given of those techniques that are nowadays widely employed in studies to advance the understanding of transport phenomena in fluids. Techniques that employ effects caused by fluid molecules are briefly treated, and examples of measurements are given to demonstrate the kind of information that can be obtained by these techniques. Optical techniques using tracers to obtain transport information are summarized, and laser-Doppler anemometry and its application to fluid flow studies are emphasized. Applications of this technique in single-phase and two-phase flows are given that demonstrate its potential in experimental fluid mechanics and convective heat transfer studies. 63 refs.

Durst, F. (Erlangen-Nuernberg Universitaet, Erlangen (Germany, F.R.))

1990-01-01T23:59:59.000Z

18

Deep Eutectic Salt Formulations Suitable as Advanced Heat Transfer Fluids  

Science Conference Proceedings (OSTI)

Concentrating solar power (CSP) facilities are comprised of many miles of fluid-filled pipes arranged in large grids with reflective mirrors used to capture radiation from the sun. Solar radiation heats the fluid which is used to produce steam necessary to power large electricity generation turbines. Currently, organic, oil-based fluid in the pipes has a maximum temperature threshold of 400 °C, allowing for the production of electricity at approximately 15 cents per kilowatt hour. The DOE hopes to foster the development of an advanced heat transfer fluid that can operate within higher temperature ranges. The new heat transfer fluid, when used with other advanced technologies, could significantly decrease solar electricity cost. Lower costs would make solar thermal electricity competitive with gas and coal and would offer a clean, renewable source of energy. Molten salts exhibit many desirable heat transfer qualities within the range of the project objectives. Halotechnics developed advanced heat transfer fluids (HTFs) for application in solar thermal power generation. This project focused on complex mixtures of inorganic salts that exhibited a high thermal stability, a low melting point, and other favorable characteristics. A high-throughput combinatorial research and development program was conducted in order to achieve the project objective. Over 19,000 candidate formulations were screened. The workflow developed to screen various chemical systems to discover salt formulations led to mixtures suitable for use as HTFs in both parabolic trough and heliostat CSP plants. Furthermore, salt mixtures which will not interfere with fertilizer based nitrates were discovered. In addition for use in CSP, the discovered salt mixtures can be applied to electricity storage, heat treatment of alloys and other industrial processes.

Raade, Justin; Roark, Thomas; Vaughn, John; Bradshaw, Robert

2013-07-22T23:59:59.000Z

19

Combustion Simulations [Heat Transfer and Fluid Mechanics] - Nuclear  

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

Combustion Simulations Combustion Simulations Capabilities Engineering Computation and Design Engineering and Structural Mechanics Systems/Component Design, Engineering and Drafting Heat Transfer and Fluid Mechanics Overview Thermal Hydraulic Optimization of Nuclear Systems Underhood Thermal Management Combustion Simulations Advanced Model and Methodology Development Multi-physics Reactor Performance and Safety Simulations Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Heat Transfer and Fluid Mechanics Bookmark and Share Combustion Simulations Density Distribution of Spray in Near-Injector Region Density Distribution of Spray in Near-Injector Region. Click on image to view larger image. Development of computer models based on Front-Tracking and

20

SunShot Initiative: Advanced Heat Transfer Fluids and Novel Thermal...  

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

Advanced Heat Transfer Fluids and Novel Thermal Storage Concepts for CSP Generation to someone by E-mail Share SunShot Initiative: Advanced Heat Transfer Fluids and Novel Thermal...

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


21

High Operating Temperature Liquid Metal Heat Transfer Fluids  

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

Liquid Metal Liquid Metal Heat Transfer Fluids UCLA, UCB, Yale DE-EE0005941 | April 15, 2013 | Ju 1.1 Thermochemistry modeling * Continue CALPHAD based calculations to search for optimal ternary alloy compositions. * Initiate development of liquid density models. 1.2 Combinatorial synthesis and characterization * Pipe-Liquid interaction of compositional library * More alloys, alloy additions and effect on liquidus temperatures * Iteratively optimize the compositions. 1.3 Corrosion characterization and mitigation * Tune static corrosion testing systems for testing over an extended period of time. * Perform analysis of the micro mechanical testing on the oxide layers. 1.4 Heat transfer characterization and modeling * Complete the construction of the flow loop and perform experiments to measure

22

Advanced Heat Transfer Fluids for Concentrated Solar Power (CSP)  

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

Science Science Computing, Environment & Life Sciences Energy Engineering & Systems Analysis Photon Sciences Physical Sciences & Engineering Energy Frontier Research Centers Science Highlights Postdoctoral Researchers Advanced Heat Transfer Fluids for Concentrated Solar Power (CSP) Applications November 1, 2011 Tweet EmailPrint The current levelized cost of energy (LCOE) from concentrated solar power (CSP) is ~ $0.11/kWh. The U.S. Department of Energy has set goals to reduce this cost to ~$0.07/kWh with 6 hours of storage by 2015 and to ~$0.05/kWh with 16 hours of storage by 2020. To help meet these goals, scientists at Argonne National Laboratory are working to improve the overall CSP plant efficiency by enhancing the thermophysical properties of heat transfer

23

Heat Transfer Fluids for Solar Water Heating Systems | Department...  

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

exchanger. | Photo from iStockphoto.com Heat Exchangers for Solar Water Heating Systems Rooftop solar water heaters need regular maintenance to operate at peak efficiency. |...

24

Low-melting point inorganic nitrate salt heat transfer fluid  

DOE Patents (OSTI)

A low-melting point, heat transfer fluid made of a mixture of four inorganic nitrate salts: 9-18 wt % NaNO.sub.3, 40-52 wt % KNO.sub.3, 13-21 wt % LiNO.sub.3, and 20-27 wt % Ca(NO.sub.3).sub.2. These compositions can have liquidus temperatures less than 100 C; thermal stability limits greater than 500 C; and viscosity in the range of 5-6 cP at 300 C; and 2-3 cP at 400 C.

Bradshaw, Robert W. (Livermore, CA); Brosseau, Douglas A. (Albuquerque, NM)

2009-09-15T23:59:59.000Z

25

A composite grid solver for conjugate heat transfer in fluid-structure systems  

Science Conference Proceedings (OSTI)

We describe a numerical method for modeling temperature-dependent fluid flow coupled to heat transfer in solids. This approach to conjugate heat transfer can be used to compute transient and steady state solutions to a wide range of fluid-solid systems ... Keywords: Conjugate heat transfer, Incompressible flow, Multi-domain solvers, Numerical methods, Overlapping grids

William D. Henshaw; Kyle K. Chand

2009-06-01T23:59:59.000Z

26

Heat Transfer Fluids Containing Nanoparticles (08-066)  

The issue of heat transfer offers fertile ground for scientific exploration across many disciplines. Argonne researchers have discovered the potential ...

27

A Mountain-Scale Thermal Hydrologic Model for Simulating Fluid Flow and Heat Transfer in Unsaturated Fractured Rock  

E-Print Network (OSTI)

fluid flow and heat-transfer processes. The physicalcoupled fluid-flow and heat-transfer processes has proven toin which flow and heat transfer processes along drifts are

Wu, Yu-Shu; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, Gudmundur S.

2005-01-01T23:59:59.000Z

28

Molten salt as a heat transfer fluid for heating a subsurface formation  

DOE Patents (OSTI)

A heating system for a subsurface formation includes a conduit located in an opening in the subsurface formation. An insulated conductor is located in the conduit. A material is in the conduit between a portion of the insulated conductor and a portion of the conduit. The material may be a salt. The material is a fluid at operating temperature of the heating system. Heat transfers from the insulated conductor to the fluid, from the fluid to the conduit, and from the conduit to the subsurface formation.

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

2010-11-16T23:59:59.000Z

29

Design and evaluation of heat transfer fluids for direct immersion cooling of electronic systems .  

E-Print Network (OSTI)

??Comprehensive molecular design was used to identify new heat transfer fluids for direct immersion phase change cooling of electronic systems. Four group contribution methods for… (more)

Harikumar Warrier, Pramod Kumar Warrier

2012-01-01T23:59:59.000Z

30

Center for Energy Efficiency and Renewable Energy at University of Massachusetts 3D Model of Heat Transfer and Fluid3D Model of Heat Transfer and Fluid  

E-Print Network (OSTI)

Center for Energy Efficiency and Renewable Energy at University of Massachusetts 3D Model of Heat for Energy Efficiency and Renewable Energy at University of Massachusetts 3D Model of Heat Transfer and Fluid WindowModeling a 3D Window Future WorkFuture Work #12;Center for Energy Efficiency and Renewable Energy

Massachusetts at Amherst, University of

31

DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 1  

Science Conference Proceedings (OSTI)

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.

Not Available

1992-06-01T23:59:59.000Z

32

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

Science Conference Proceedings (OSTI)

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.

Not Available

1992-06-01T23:59:59.000Z

33

DOE Fundamentals Handbook: Thermodynamics, Heat Transfer, and Fluid Flow, Volume 3  

SciTech Connect

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.

Not Available

1992-06-01T23:59:59.000Z

34

Heat transfer in porous media with fluid phase changes  

DOE Green Energy (OSTI)

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

Su, H.J.

1981-06-01T23:59:59.000Z

35

THERMOPHYSICAL PROPERTIES OF NANOPARTICLE-ENHANCED IONIC LIQUIDS HEAT TRANSFER FLUIDS  

SciTech Connect

An experimental investigation was completed on nanoparticle enhanced ionic liquid heat transfer fluids as an alternative to conventional organic based heat transfer fluids (HTFs). These nanoparticle-based HTFs have the potential to deliver higher thermal conductivity than the base fluid without a significant increase in viscosity at elevated temperatures. The effect of nanoparticle morphology and chemistry on thermophysical properties was examined. Whisker shaped nanomaterials were found to have the largest thermal conductivity temperature dependence and were also less likely to agglomerate in the base fluid than spherical shaped nanomaterials.

Fox, E.

2013-04-15T23:59:59.000Z

36

Numerical simulation of fluid flow and heat transfer in a water heater  

Science Conference Proceedings (OSTI)

Energy consumption represents a major concern, considering the limited resources and latest targets for lower emissions of carbon dioxide. Therefore design of electric heating elements for household and industry are more and more subject to optimization, ... Keywords: electric heating, finite elements, fluid flow, heat transfer

Mircea Nicoar?; Aurel R?du??; Lauren?iu Roland Cucuruz; Cosmin Locovei

2010-04-01T23:59:59.000Z

37

Two-dimensional computational fluid dynamics and conduction simulations of heat transfer in window frames with internal cavities - Part 1: Cavities only  

E-Print Network (OSTI)

of heat fluxes from CFD and conduction simulations for theapproach to solve the conduction heat-transfer equation. TheFluid Dynamics and Conduction Simulations of Heat Transfer

Gustavsen, Arild; Kohler, Christian; Arasteh, Dariush; Curcija, Dragan

2003-01-01T23:59:59.000Z

38

HEAT TRANSFER IN POROUS MEDIA WITH FLUID PHASE CHANGES  

E-Print Network (OSTI)

Cotter, T. P. : "Theory of Heat Pipe," Report No. LA-3246-L. : "Two Component Heat Pipes, It Propress in Astronauticsthe successful. The 'heat pipe ph periments were quite

Su, Ho-Jeen.

2010-01-01T23:59:59.000Z

39

HEAT TRANSFER IN POROUS MEDIA WITH FLUID PHASE CHANGES  

E-Print Network (OSTI)

percent compared with heat conduction alone. likely to occurThus, in addition to heat conduction, a large amount ofFourier's law for heat conduction, and the mass balance and

Su, Ho-Jeen.

2010-01-01T23:59:59.000Z

40

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

E-Print Network (OSTI)

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

Shiralkar, B. S.

1968-01-01T23:59:59.000Z

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


41

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

DOE Green Energy (OSTI)

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.

Not Available

2012-12-01T23:59:59.000Z

42

Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients  

DOE Green Energy (OSTI)

Effect of Mixed Working Fluid Composition on Binary Cycle Condenser Heat Transfer Coefficients Dan Wendt, Greg Mines Idaho National Laboratory The use of mixed working fluids in binary power plants can provide significant increases in plant performance, provided the heat exchangers are designed to take advantage of these fluids non-isothermal phase changes. In the 1980's testing was conducted at DOE's Heat Cycle Research Facility (HCRF) where mixtures of different compositions were vaporized at supercritical pressures and then condensed. This testing had focused on using the data collected to verify that Heat Transfer Research Incorporated (HTRI) codes were suitable for the design of heat exchangers that could be used with mixtures. The HCRF data includes mixture compositions varying from 0% to 40% isopentane and condenser tube orientations of 15{sup o}, 60{sup o}, and 90{sup o} from horizontal. Testing was performed over a range of working fluid and cooling fluid conditions. Though the condenser used in this testing was water cooled, the working fluid condensation occurred on the tube-side of the heat exchanger. This tube-side condensation is analogous to that in an air-cooled condenser. Tube-side condensing heat transfer coefficient information gleaned from the HCRF testing is used in this study to assess the suitability of air-cooled condenser designs for use with mixtures. Results of an air-cooled binary plant process model performed with Aspen Plus indicate that that the optimal mixture composition (producing the maximum net power for the scenario considered) is within the range of compositions for which data exist. The HCRF data is used to assess the impact of composition, tube orientation, and process parameters on the condensing heat transfer coefficients. The sensitivity of the condensing coefficients to these factors is evaluated and the suitability of air-cooled condenser designs with mixtures is assessed. This paper summarizes the evaluation of the HCRF data and discusses the next steps in the project evaluation of air-cooled condenser designs that can take advantage of the performance gains possible with these fluids.

Dan Wendt; Greg Mines

2011-10-01T23:59:59.000Z

43

ON THE TRANSFER OF HEAT TO FLUIDS FLOWING THROUGH PIPES, ANNULI, AND PARALLEL PLATES  

SciTech Connect

Nusselt numbers were calculated for heat transfer to fluids flowing through annuli under conditions of uniform heat flux and fully established velocity and temperature profiles. The following cases were considered: (a) laminar flow, (b) slug flow, (c) turbulent flow with molecular conduction only, and (d) turbulent flow with both molecular and eddy conduction. These Nusselt numbers were determined for two conditions: heat transfer from the inner wall only and heat transfer from the outer wall only. The results were correlated by semi-empirical equations. The final results obtained on cases (a), (b), amd (c) are applicable to any fluid, whereas those obtained on (d) are for liquid metals only. Wall- and bulk-temperature relationships for the above four cases were also determined. These relationships were treated as dimensionless temperature ratios. Both the Nusselt numbers ad temperature ratios were evaluated over the r/ sub 1//r/sub 2/ range, zero to unity; the former being the case of the circular pipe, and the later, the case of infinite parallel plates. (auth)

Dwyer, O.E.

1963-01-01T23:59:59.000Z

44

Thermal Performance of a Novel Heat Transfer Fluid Containing Multiwalled Carbon Nanotubes and Microencapsulated Phase Change Materials  

E-Print Network (OSTI)

The present research work aims to develop a new heat transfer fluid by combining multiwalled carbon nanotubes (MWCNT) and microencapsulated phase change materials (MPCMs). Stable nanofluids have been prepared using different sizes of multiwalled carbon nanotubes and their properties like thermal conductivity and viscosity have been measured. Microencapsulated phase change material slurries containing microcapsules of octadecane have been purchased from Thies Technology Inc. Tests have been conducted to determine the durability and viscosity of the MPCM slurries. Heat transfer experiments have been conducted to determine the heat transfer coefficients and pressure drop of the MWCNT nanofluids and MPCM slurries under turbulent flow and constant heat flux conditions. The MPCM slurry and the MWCNT nanofluid have been combined to form a new heat transfer fluid. Heat transfer tests have been conducted to determine the heat transfer coefficient and the pressure drop of the new fluid under turbulent flow and constant heat flux conditions. The potential use of this fluid in convective heat transfer applications has also been discussed. The heat transfer results of the MPCM slurry containing octadecane microcapsules was in good agreement with the published literature. The thermal conductivity enhancement obtained for MWCNTs with diameter (60-100 nm) and length (0.5-40?m) was 8.11%. The maximum percentage enhancement (compared to water) obtained in the heat transfer coefficient of the MWCNT nanofluid was in the range of 20-25%. The blend of MPCMs and MWCNTs was highly viscous and displayed a shear thinning behavior. Due to its high viscosity, the flow became laminar and the heat transfer performance was lowered. It was interesting to observe that the value of the maximum local heat transfer coefficient achieved in the case of the blend (laminar flow), was comparable to that obtained in the case of the MPCM slurry (turbulent flow). The pressure drop of the blend was lower than that of the MWCNT nanofluid.

Tumuluri, Kalpana

2010-05-01T23:59:59.000Z

45

Gas Turbine/Solar Parabolic Trough Hybrid Design Using Molten Salt Heat Transfer Fluid: Preprint  

DOE Green Energy (OSTI)

Parabolic trough power plants can provide reliable power by incorporating either thermal energy storage (TES) or backup heat from fossil fuels. This paper describes a gas turbine / parabolic trough hybrid design that combines a solar contribution greater than 50% with gas heat rates that rival those of natural gas combined-cycle plants. Previous work illustrated benefits of integrating gas turbines with conventional oil heat-transfer-fluid (HTF) troughs running at 390?C. This work extends that analysis to examine the integration of gas turbines with salt-HTF troughs running at 450 degrees C and including TES. Using gas turbine waste heat to supplement the TES system provides greater operating flexibility while enhancing the efficiency of gas utilization. The analysis indicates that the hybrid plant design produces solar-derived electricity and gas-derived electricity at lower cost than either system operating alone.

Turchi, C. S.; Ma, Z.

2011-08-01T23:59:59.000Z

46

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

SciTech Connect

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)

Tao, Y.B.; He, Y.L. [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)

2010-10-15T23:59:59.000Z

47

Phenylnaphthalene Derivatives as Heat Transfer Fluids for Concentrating Solar Power: Loop Experiments and Final Report  

SciTech Connect

ORNL and subcontractor Cool Energy completed an investigation of higher-temperature, organic thermal fluids for solar thermal applications. Although static thermal tests showed promising results for 1-phenylnaphthalene, loop testing at temperatures to 450 C showed that the material isomerized at a slow rate. In a loop with a temperature high enough to drive the isomerization, the higher melting point byproducts tended to condense onto cooler surfaces. So, as experienced in loop operation, eventually the internal channels of cooler components such as the waste heat rejection exchanger may become coated or clogged and loop performance will decrease. Thus, pure 1-phenylnaphthalene does not appear to be a fluid that would have a sufficiently long lifetime (years to decades) to be used in a loop at the increased temperatures of interest. Hence a decision was made not to test the ORNL fluid in the loop at Cool Energy Inc. Instead, Cool Energy tested and modeled power conversion from a moderate-temperature solar loop using coupled Stirling engines. Cool Energy analyzed data collected on third and fourth generation SolarHeart Stirling engines operating on a rooftop solar field with a lower temperature (Marlotherm) heat transfer fluid. The operating efficiencies of the Stirling engines were determined at multiple, typical solar conditions, based on data from actual cycle operation. Results highlighted the advantages of inherent thermal energy storage in the power conversion system.

McFarlane, Joanna [ORNL; Bell, Jason R [ORNL; Felde, David K [ORNL; Joseph III, Robert Anthony [ORNL; Qualls, A L [ORNL; Weaver, Samuel P [ORNL

2013-02-01T23:59:59.000Z

48

Laminar Flow Forced Convection Heat Transfer Behavior of Phase Change Material Fluid in Straight and Staggered Pin Microchannels  

E-Print Network (OSTI)

Microchannels have been studied extensively for electronic cooling applications ever since they were found to be effective in removing high heat flux from small areas. The rate of heat removed using microchannels depends on many factors including 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 so far in using Phase Change Material (PCM) fluids and pin fins in microchannels to enhance the heat transfer. PCM fluids exhibit greater heat transfer when the phase change material undergoes liquid-to-solid transformation. Staggered pins in microchannels have also shown higher heat removal characteristics because of the continuous breaking and formation of the thermal and hydrodynamic boundary layer; they also exhibit higher pressure drop because pins act as flow obstructers. This paper presents numerical results of circular, square, straight rectangular microchannels with various aspect ratios (1:2, 1:4 and 1:8), and rectangular microchannels with two characteristic staggered pins (square and circular, fixed height with no variation in aspect ratio). The heat transfer performance of a single phase fluid and PCM fluid in all of these microchannels and the corresponding pressure drop characteristics are also presented. An effective specific heat capacity model was used to account for the phase change process of PCM fluid. Comparison of heat transfer characteristics of single phase fluid and PCM fluid are presented for all the geometries considered. Among the straight microchannels, 1:8 geometry was found to have the highest Nusselt number. The use of PCM fluid in straight microchannels increased the Nusselt number by 3-7 percent compared to the single phase fluids. Among the staggered pin microchannels, circular pins were found to be more effective in terms of heat transfer by exhibiting higher Nusselt number. Circular pin microchannels were also found to have lower pressure drop compared to the square pin microchannels. Overall, for all the geometries considered, it was found that the PCM fluid enhances the heat transfer compared to the SPF fluid.

Kondle, Satyanarayana

2010-08-01T23:59:59.000Z

49

THE POTENTIAL OF NANOPARTICLE ENHANCED IONIC LIQUIDS (NEILS) AS ADVANCED HEAT TRANSFER FLUIDS  

DOE Green Energy (OSTI)

Interest in capturing the energy of the sun is rising as demands for renewable energy sources increase. One area of developing research is the use of concentrating solar power (CSP), where the solar energy is concentrated by using mirrors to direct the sunlight towards a collector filled with a heat transfer fluid (HTF). The HTF transfers the collected energy into pressurized steam, which is used to generate energy. The greater the energy collected by the HTF, the more efficent the electrical energy production is, thus the overall efficiency is controlled by the thermal fluid. Commercial HTFs such as Therminol{reg_sign} (VP-1), which is a blend of biphenyl and diphenyl oxide, have a significant vapor pressure, especially at elevated temperatures. In order for these volatile compounds to be used in CSP systems, the system either has to be engineered to prevent the phase change (i.e., volatilization and condensation) through pressurization of the system, or operate across the phase change. Over thirty years ago, a class of low-melting organic compounds were developed with negligible vapor pressure. These compounds are referred to as ionic liquids (ILs), which are organic-based compounds with discrete charges that cause a significant decrease in their vapor pressure. As a class, ILs are molten salts with a melting point below 100 C and can have a liquidus range approaching 400 C, and in several cases freezing points being below 0 C. Due to the lack of an appreciable vapor pressure, volatilization of an IL is not possible at atmospheric pressure, which would lead to a simplification of the design if used as a thermal fluid and for energy storage materials. Though the lack of a vapor pressure does not make the use of ILs a better HTF, the lack of a vapor pressure is a compliment to their higher heat capacity, higher volummetric density, and thus higher volumetric heat capacity. These favorable physical properties give ILs a pontential advantage over the current commerically used thermal fluids. Also within the past decade nanofluids have gained attention for thermal conductivity enhancment of fluids, but little analysis has been completed on the heat capacity effects of the nanoparticle addition. The idea of ILs or nanofluids as a HTF is not new, as there are several references that have proposed the idea. However, the use of ionic liquid nanofluids containing nanomaterials other than carbon nanotubes has never before been studied. Here, for the first time, nano-particle enhanced ILs (NEILs) have been shown to increase the heat capacity of the IL with no adverse side effects to the ILs thermal stability and, only at high nanoparticle loading, are the IL physical properties affected. An increase of volumetric heat capacity translates into a better heat transfer fluid as more energy is stored per volumetric unit in the solar concentrating section, thus more efficency in increased steam pressure. Results show that the properties of the NEIL are highly dependant on the suspended nanomaterial and careful materials selection is required to fully optimize the nanofluid properties.

Fox, E.; Bridges, N.; Visser, A.

2011-09-14T23:59:59.000Z

50

LONG TERM THERMAL STABILITY IN AIR OF IONIC LIQUID BASED ALTERNATIVE HEAT TRANSFER FLUIDS FOR CLEAN ENERGY PRODUCTION  

Science Conference Proceedings (OSTI)

The purpose of this study was to investigate the effect of long-term aging on the thermal stability and chemical structure of seven different ILs so as to explore their suitability for use as a heat transfer fluid. This was accomplished by heating the ILs for 15 weeks at 200°C in an oxidizing environment and performing subsequent analyses on the aged chemicals.

Fox, E.

2012-10-15T23:59:59.000Z

51

Long Term Thermal Stability In Air Of Ionic Liquid Based Alternative Heat Transfer Fluids For Clean Energy Production  

SciTech Connect

The purpose of this study was to investigate the effect of long-term aging on the thermal stability and chemical structure of seven different ILs so as to explore their suitability for use as a heat transfer fluid. This was accomplished by heating the ILs for 15 weeks at 200?C in an oxidizing environment and performing subsequent analyses on the aged chemicals.

2012-10-15T23:59:59.000Z

52

DOE-HDBK-1012/2-92; DOE Fundamentals Handbook Thermodynamics, Heat Transfer, and Fluid Flow Volume 2 of 3  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

2-92 2-92 JUNE 1992 DOE FUNDAMENTALS HANDBOOK THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW Volume 2 of 3 U.S. Department of Energy FSC-6910 Washington, D.C. 20585 Distribution Statement A. Approved for public release; distribution is unlimited. This document has been reproduced directly from the best available copy. Available to DOE and DOE contractors from the Office of Scientific and Technical Information. P. O. Box 62, Oak Ridge, TN 37831; prices available from (615) 576- 8401. FTS 626-8401. Available to the public from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, VA 22161. Order No. DE92019790 THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW Rev. 0 HT ABSTRACT The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was

53

DOE-HDBK-1012/1-92; DOE Fundamentals Handbook Thermodynamics, Heat Transfer, and Fluid Flow Volume 1 of 3  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

1-92 1-92 JUNE 1992 DOE FUNDAMENTALS HANDBOOK THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW Volume 1 of 3 U.S. Department of Energy FSC-6910 Washington, D.C. 20585 Distribution Statement A. Approved for public release; distribution is unlimited. This document has been reproduced directly from the best available copy. Available to DOE and DOE contractors from the Office of Scientific and Technical Information. P. O. Box 62, Oak Ridge, TN 37831; (615) 576-8401. Available to the public from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, VA 22161. Order No. DE92019789 THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW Rev. 0 HT ABSTRACT The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was developed to assist nuclear facility operating contractors provide operators, maintenance

54

DOE-HDBK-1012/3-92; DOE Fundamentals Handbook Thermodynamics, Heat Transfer, and Fluid Flow Volume 3 of 3  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

3-92 3-92 JUNE 1992 DOE FUNDAMENTALS HANDBOOK THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW Volume 3 of 3 U.S. Department of Energy FSC-6910 Washington, D.C. 20585 Distribution Statement A. Approved for public release; distribution is unlimited. This document has been reproduced directly from the best available copy. Available to DOE and DOE contractors from the Office of Scientific and Technical Information. P. O. Box 62, Oak Ridge, TN 37831; prices available from (615) 576- 8401. FTS 626-8401. Available to the public from the National Technical Information Service, U.S. Department of Commerce, 5285 Port Royal Rd., Springfield, VA 22161. Order No. DE92019791 THERMODYNAMICS, HEAT TRANSFER, AND FLUID FLOW Rev. 0 HT ABSTRACT The Thermodynamics, Heat Transfer, and Fluid Flow Fundamentals Handbook was

55

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities  

E-Print Network (OSTI)

the two-dimensional heat transfer through building products.Gustavsen, A. 2001. Heat transfer in window frames withand CFD Simulations of Heat Transfer in Horizontal Window

Gustavsen, Arlid

2008-01-01T23:59:59.000Z

56

Optimization of Phase Change Heat Transfer in Biporous Media  

E-Print Network (OSTI)

Aspectcs of Boiling Heat Transfer”. PhD Thesis dissertation,Celled Foams”. Numerical Heat Transfer, Vol. 54, issue 1,Dimensional Fluid Flow and Heat Transfer”. Numerical Heat

Reilly, Sean

2013-01-01T23:59:59.000Z

57

Heat Transfer and Fluid Flow of Benard-Cell Convection in Rectangular Container with Free Surface Sensed by Infrared Thermography  

Science Conference Proceedings (OSTI)

The natural convection flow phenomena that occur inside an enclosed space are very interesting examples of complex fluid systems that may yield to analytical, empirical and numerical solutions, and many reports have looked into this basic problem. In ... Keywords: Gas-liquid Interface, Heat Transfer, Infrared Thermography, Natural Convection, Thermal Visualization, Turbulence

T. Inagaki; M. Hatori; T. Suzuki; Y. Shiina

2006-04-01T23:59:59.000Z

58

Enhanced heat transfer using nanofluids  

DOE Patents (OSTI)

This invention is directed to a method of and apparatus for enhancing heat transfer in fluids such as deionized water. ethylene glycol, or oil by dispersing nanocrystalline particles of substances such as copper, copper oxide, aluminum oxide, or the like in the fluids. Nanocrystalline particles are produced and dispersed in the fluid by heating the substance to be dispersed in a vacuum while passing a thin film of the fluid near the heated substance. The fluid is cooled to control its vapor pressure.

Choi, Stephen U. S. (Lisle, IL); Eastman, Jeffrey A. (Naperville, IL)

2001-01-01T23:59:59.000Z

59

A Mountain-Scale Thermal Hydrologic Model for Simulating Fluid Flow and Heat Transfer in Unsaturated Fractured Rock  

E-Print Network (OSTI)

for Modeling Fluid and Heat Flow in Fractured Porous Media,with fluid and heat flow in fractured porous media arefluid and heat flow in porous media, heat pipe, reservoir simulation, fractured

Wu, Yu-Shu; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, Gudmundur S.

2005-01-01T23:59:59.000Z

60

Coupled computational fluid dynamics and heat transfer analysis of the VHTR lower plenum.  

SciTech Connect

The very high temperature reactor (VHTR) concept is being developed by the US Department of Energy (DOE) and other groups around the world for the future generation of electricity at high thermal efficiency (> 48%) and co-generation of hydrogen and process heat. This Generation-IV reactor would operate at elevated exit temperatures of 1,000-1,273 K, and the fueled core would be cooled by forced convection helium gas. For the prismatic-core VHTR, which is the focus of this analysis, the velocity of the hot helium flow exiting the core into the lower plenum (LP) could be 35-70 m/s. The impingement of the resulting gas jets onto the adiabatic plate at the bottom of the LP could develop hot spots and thermal stratification and inadequate mixing of the gas exiting the vessel to the turbo-machinery for energy conversion. The complex flow field in the LP is further complicated by the presence of large cylindrical graphite posts that support the massive core and inner and outer graphite reflectors. Because there are approximately 276 channels in the VHTR core from which helium exits into the LP and a total of 155 support posts, the flow field in the LP includes cross flow, multiple jet flow interaction, flow stagnation zones, vortex interaction, vortex shedding, entrainment, large variation in Reynolds number (Re), recirculation, and mixing enhancement and suppression regions. For such a complex flow field, experimental results at operating conditions are not currently available. Instead, the objective of this paper is to numerically simulate the flow field in the LP of a prismatic core VHTR using the Sandia National Laboratories Fuego, which is a 3D, massively parallel generalized computational fluid dynamics (CFD) code with numerous turbulence and buoyancy models and simulation capabilities for complex gas flow fields, with and without thermal effects. The code predictions for simpler flow fields of single and swirling gas jets, with and without a cross flow, are validated using reported experimental data and theory. The key processes in the LP are identified using phenomena identification and ranking table (PIRT). It may be argued that a CFD code that accurately simulates simplified, single-effect flow fields with increasing complexity is likely to adequately model the complex flow field in the VHTR LP, subject to a future experimental validation. The PIRT process and spatial and temporal discretizations implemented in the present analysis using Fuego established confidence in the validation and verification (V and V) calculations and in the conclusions reached based on the simulation results. The performed calculations included the helicoid vortex swirl model, the dynamic Smagorinsky large eddy simulation (LES) turbulence model, participating media radiation (PMR), and 1D conjugate heat transfer (CHT). The full-scale, half-symmetry LP mesh used in the LP simulation included unstructured hexahedral elements and accounted for the graphite posts, the helium jets, the exterior walls, and the bottom plate with an adiabatic outer surface. Results indicated significant enhancements in heat transfer, flow mixing, and entrainment in the VHTR LP when using swirling inserts at the exit of the helium flow channels into the LP. The impact of using various swirl angles on the flow mixing and heat transfer in the LP is qualified, including the formation of the central recirculation zone (CRZ), and the effect of LP height. Results also showed that in addition to the enhanced mixing, the swirling inserts result in negligible additional pressure losses and are likely to eliminate the formation of hot spots.

El-Genk, Mohamed S. (University of New Mexico, Albuquerque, NM); Rodriguez, Salvador B.

2010-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "heat transfer fluid" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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61

Analysis of fluid flow and heat transfer in a rib grit roughened surface solar air heater using CFD  

SciTech Connect

This paper presents the study of fluid flow and heat transfer in a solar air heater by using Computational Fluid Dynamics (CFD) which reduces time and cost. Lower side of collector plate is made rough with metal ribs of circular, square and triangular cross-section, having 60 inclinations to the air flow. The grit rib elements are fixed on the surface in staggered manner to form defined grid. The system and operating parameters studied are: e/D{sub h} = 0.044, p/e = 17.5 and l/s = 1.72, for the Reynolds number range 3600-17,000. To validate CFD results, experimental investigations were carried out in the laboratory. It is found that experimental and CFD analysis results give the good agreement. The optimization of rib geometry and its angle of attack is also done. The square cross-section ribs with 58 angle of attack give maximum heat transfer. The percentage enhancement in the heat transfer for square plate over smooth surface is 30%. (author)

Karmare, S.V. [Department of Mechanical Engineering, Government College Engineering, Karad 415 124, Maharashtra (India); Shivaji University, Kolhapur, Maharashtra (India); Tikekar, A.N. [Department of Mechanical Engineering, Walchand College of Engineering, Sangli (India); Shivaji University, Kolhapur, Maharashtra (India)

2010-03-15T23:59:59.000Z

62

Phenylnaphthalene as a Heat Transfer Fluid for Concentrating Solar Power: High-Temperature Static Experiments  

SciTech Connect

Concentrating solar power (CSP) may be an alternative to generating electricity from fossil fuels; however, greater thermodynamic efficiency is needed to improve the economics of CSP operation. One way of achieving improved efficiency is to operate the CSP loop at higher temperatures than the current maximum of about 400 C. ORNL has been investigating a synthetic polyaromatic oil for use in a trough type CSP collector, to temperatures up to 500 C. The oil was chosen because of its thermal stability and calculated low vapor and critical pressures. The oil has been synthesized using a Suzuki coupling mechanism and has been tested in static heating experiments. Analysis has been conducted on the oil after heating and suggests that there may be some isomerization taking place at 450 C, but the fluid appears to remain stable above that temperature. Tests were conducted over one week and further tests are planned to investigate stabilities after heating for months and in flow configurations. Thermochemical data and thermophysical predictions indicate that substituted polyaromatic hydrocarbons may be useful for applications that run at higher temperatures than possible with commercial fluids such as Therminol-VP1.

Bell, Jason R [ORNL; Joseph III, Robert Anthony [ORNL; McFarlane, Joanna [ORNL; Qualls, A L [ORNL

2012-05-01T23:59:59.000Z

63

Corrosion resistance of metallic solar absorber materials in a range of heat transfer fluids. Final technical report  

SciTech Connect

The work described in this report is intended to provide manufacturers, designers, and installers with reliable corrosion compatibility data, meaningful maintenance schedule, and confidence in durability and performance of solar collector units. The corrosion behavior of Cu alloy 122, Al alloy 1100, mild steel 1010, and a ferritic stainless steel (alloy 444) was determined in a variety of potential solar heat transfer fluids. The fluids included potable waters, water glycol solutions, and four non-aqueous fluids. The test apparatus cycled the temperatures of the fluids through those typical of an operating solar energy collector unit. The 444 stainless steel was the most corrosion resistant material and in uninhibited solutions demonstrated only extremely shallow pits during the 180 day test. The use of inhibited solutions generally prevented pits from forming. Cu alloy 122 showed quite low corrosion rates in uninhibited solutions although the presence of excess solder flux promoted some crevice corrosion. In such solutions, uniform, corrosive attack produced general surface roughening along with a protective surface oxide. The overall corrosion rate of the alloy was generally lower in inhibited glycol solutions although pitting within the crevice region occurred in limited cases. Exposure in the non-aqueous fluids resulted in extremely low corrosion rates with little evidence of localized attack.

Brock, A.J.; Smith, E.F. III

1983-01-01T23:59:59.000Z

64

Handbook of heat transfer applications (2nd edition)  

Science Conference Proceedings (OSTI)

The applications of heat transfer in engineering problems are considered. Among the applications discussed are: mass transfer cooling; heat exchangers; and heat pipes. Consideration is also given to: heat transfer in nonNewtonian fluids; fluidized and packed beds; thermal energy storage; and heat transfer in solar collectors. Additional topics include: heat transfer in buildings; cooling towers and ponds; and geothermal heat transfer.

Rohsenow, W.M.; Hartnett, J.P.; Ganic, E.N.

1985-01-01T23:59:59.000Z

65

Heat Capacity Uncertainty Calculation for the Eutectic Mixture of Biphenyl/Diphenyl Ether Used as Heat Transfer Fluid: Preprint  

DOE Green Energy (OSTI)

The main objective of this study was to calculate the uncertainty at 95% confidence for the experimental values of heat capacity of the eutectic mixture of biphenyl/diphenyl ether (Therminol VP-1) determined from 300 to 370 degrees C. Twenty-five samples were evaluated using differential scanning calorimetry (DSC) to obtain the sample heat flow as a function of temperature. The ASTM E-1269-05 standard was used to determine the heat capacity using DSC evaluations. High-pressure crucibles were employed to contain the sample in the liquid state without vaporizing. Sample handling has a significant impact on the random uncertainty. It was determined that the fluid is difficult to handle, and a high variability of the data was produced. The heat capacity of Therminol VP-1 between 300 and 370 degrees C was measured to be equal to 0.0025T+0.8672 with an uncertainty of +/- 0.074 J/g.K (3.09%) at 95% confidence with T (temperature) in Kelvin.

Gomez, J. C.; Glatzmaier, G. C.; Mehos, M.

2012-09-01T23:59:59.000Z

66

Heat transfer and fluid flow characteristics of microchannels with internal longitudinal fins.  

E-Print Network (OSTI)

??Electronic components generate large amount of heat during their operation, which requires to be dissipated. Over the past decade, internal heat generation levels have exponentially… (more)

Foong, Andrew Jun Li

2009-01-01T23:59:59.000Z

67

Heat transfer. [heat transfer roller employing a heat pipe  

SciTech Connect

A heat transfer roller embodying a heat pipe is disclosed. The heat pipe is mounted on a shaft, and the shaft is adapted for rotation on its axis.

Sarcia, D.S.

1978-05-23T23:59:59.000Z

68

Two-Dimensional Computational Fluid Dynamics and Conduction Simulations of Heat Transfer in Horizontal Window Frames with Internal Cavities  

E-Print Network (OSTI)

2001. Heat transfer in window frames with internal cavities.Simulations of Internal Window Frame Cavities Validatedin Three-Dimensional Window Frames with Internal Cavities. ”

Gustavsen, Arlid

2008-01-01T23:59:59.000Z

69

Heat transfer system  

DOE Patents (OSTI)

A heat transfer system for a nuclear reactor is described. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

Not Available

1980-03-07T23:59:59.000Z

70

Heat transfer system  

DOE Patents (OSTI)

A heat transfer system for a nuclear reactor. Heat transfer is accomplished within a sealed vapor chamber which is substantially evacuated prior to use. A heat transfer medium, which is liquid at the design operating temperatures, transfers heat from tubes interposed in the reactor primary loop to spaced tubes connected to a steam line for power generation purposes. Heat transfer is accomplished by a two-phase liquid-vapor-liquid process as used in heat pipes. Condensible gases are removed from the vapor chamber through a vertical extension in open communication with the chamber interior.

McGuire, Joseph C. (Richland, WA)

1982-01-01T23:59:59.000Z

71

Development of Molten-Salt Heat Transfer Fluid Technology for Parabolic Trough Solar Power Plants - Public Final Technical Report  

SciTech Connect

Executive Summary This Final Report for the "Development of Molten-Salt Heat Transfer Fluid (HTF) Technology for Parabolic Trough Solar Power Plants” describes the overall project accomplishments, results and conclusions. Phase 1 analyzed the feasibility, cost and performance of a parabolic trough solar power plant with a molten salt heat transfer fluid (HTF); researched and/or developed feasible component options, detailed cost estimates and workable operating procedures; and developed hourly performance models. As a result, a molten salt plant with 6 hours of storage was shown to reduce Thermal Energy Storage (TES) cost by 43.2%, solar field cost by 14.8%, and levelized cost of energy (LCOE) by 9.8% - 14.5% relative to a similar state-of-the-art baseline plant. The LCOE savings range met the project’s Go/No Go criteria of 10% LCOE reduction. Another primary focus of Phase 1 and 2 was risk mitigation. The large risk areas associated with a molten salt parabolic trough plant were addressed in both Phases, such as; HTF freeze prevention and recovery, collector components and piping connections, and complex component interactions. Phase 2 analyzed in more detail the technical and economic feasibility of a 140 MWe,gross molten-salt CSP plant with 6 hours of TES. Phase 2 accomplishments included developing technical solutions to the above mentioned risk areas, such as freeze protection/recovery, corrosion effects of applicable molten salts, collector design improvements for molten salt, and developing plant operating strategies for maximized plant performance and freeze risk mitigation. Phase 2 accomplishments also included developing and thoroughly analyzing a molten salt, Parabolic Trough power plant performance model, in order to achieve the project cost and performance targets. The plant performance model and an extensive basic Engineering, Procurement, and Construction (EPC) quote were used to calculate a real levelized cost of energy (LCOE) of 11.50¢/kWhe , which achieved the Phase 2 Go/No Go target of less than 0.12¢/kWhe. Abengoa Solar has high confidence that the primary risk areas have been addressed in the project and a commercial plant utilizing molten salt is economically and technically feasible. The strong results from the Phase 1 and 2 research, testing, and analyses, summarized in this report, led Abengoa Solar to recommend that the project proceed to Phase 3. However, a commercially viable collector interconnection was not fully validated by the end of Phase 2, combined with the uncertainty in the federal budget, forced the DOE and Abengoa Solar to close the project. Thus the resources required to construct and operate a molten salt pilot plant will be solely supplied by Abengoa Solar.

Grogan, Dylan C. P.

2013-08-15T23:59:59.000Z

72

Effect of Working Fluid and Fluid Loading on the Performance of Rotating Heat Pipes.  

E-Print Network (OSTI)

?? The steady state heat transfer performance of axially rotating heat pipes with methanol, ethanol and water as working fluid was measured for rotational speeds… (more)

Home, Deepayan

2004-01-01T23:59:59.000Z

73

Convection Heat Transfer  

Science Conference Proceedings (OSTI)

...Heat-Transfer Equations, Fundamentals of Modeling for Metals Processing, Vol 22A, ASM Handbook, ASM International, 2009, p 625â??658...

74

Heat transfer dynamics  

Science Conference Proceedings (OSTI)

As heat transfer technology increases in complexity, it becomes more difficult for those without thermal dynamics engineering training to choose between competitive heat transfer systems offered to meet their drying requirements. A step back to the basics of heat transfer can help professional managers and papermakers make informed decisions on alternative equipment and methods. The primary forms of heat and mass transfer are reviewed with emphasis on the basics, so a practical understanding of each is gained. Finally, the principles and benefits of generating infrared energy by combusting a gaseous hydrocarbon fuel are explained.

Smith, T.M. (Marsden, Inc., Pennsauken, NJ (United States))

1994-08-01T23:59:59.000Z

75

Computational fluid dynamics analyses of lateral heat conduction, coolant azimuthal mixing and heat transfer predictions in a BR2 fuel assembly geometry.  

SciTech Connect

To support the analyses related to the conversion of the BR2 core from highly-enriched (HEU) to low-enriched (LEU) fuel, the thermal-hydraulics codes PLTEMP and RELAP-3D are used to evaluate the safety margins during steady-state operation (PLTEMP), as well as after a loss-of-flow, loss-of-pressure, or a loss of coolant event (RELAP). In the 1-D PLTEMP and RELAP simulations, conduction in the azimuthal and axial directions is not accounted. The very good thermal conductivity of the cladding and the fuel meat and significant temperature gradients in the lateral directions (axial and azimuthal directions) could lead to a heat flux distribution that is significantly different than the power distribution. To evaluate the significance of the lateral heat conduction, 3-D computational fluid dynamics (CFD) simulations, using the CFD code STAR-CD, were performed. Safety margin calculations are typically performed for a hot stripe, i.e., an azimuthal region of the fuel plates/coolant channel containing the power peak. In a RELAP model, for example, a channel between two plates could be divided into a number of RELAP channels (stripes) in the azimuthal direction. In a PLTEMP model, the effect of azimuthal power peaking could be taken into account by using engineering factors. However, if the thermal mixing in the azimuthal direction of a coolant channel is significant, a stripping approach could be overly conservative by not taking into account this mixing. STAR-CD simulations were also performed to study the thermal mixing in the coolant. Section II of this document presents the results of the analyses of the lateral heat conduction and azimuthal thermal mixing in a coolant channel. Finally, PLTEMP and RELAP simulations rely on the use of correlations to determine heat transfer coefficients. Previous analyses showed that the Dittus-Boelter correlation gives significantly more conservative (lower) predictions than the correlations of Sieder-Tate and Petukhov. STAR-CD 3-D simulations were performed to compare heat transfer predictions from CFD and the correlations. Section III of this document presents the results of this analysis.

Tzanos, C. P.; Dionne, B. (Nuclear Engineering Division)

2011-05-23T23:59:59.000Z

76

Applied heat transfer  

Science Conference Proceedings (OSTI)

Heat transfer principles are discussed with emphasis on the practical aspects of the problems. Correlations for heat transfer and pressure drop from several worldwide sources for flow inside and outside of tubes, including finned tubes are presented, along with design and performance calculations of heat exchangers economizers, air heaters, condensers, waste-heat boilers, fired heaters, superheaters, and boiler furnaces. Vibration analysis for tube bundles and heat exchangers are also discussed, as are estimating gas-mixture properties at atmospheric and elevated pressures and life-cycle costing techniques. (JMT)

Ganapathy, V.

1982-01-01T23:59:59.000Z

77

Flammability and Combustion Behaviors in Aerosols Formed by Industrial Heat Transfer Fluids Produced by the Electrospray Method  

E-Print Network (OSTI)

The existence of flammable aerosols presents a high potential for fire hazards in the process industry. Various industrial fluids, most of which operate at elevated temperatures and pressures, can be atomized when released under high pressure through a small orifice. Because of the complexity in the process of aerosol formation and combustion, the availability of data on aerosol flammability and flame propagation behaviors is still quite limited, making it difficult to evaluate the potential fire and explosion risks from released aerosols in the process industry and develop safety measures for preventing and/or mitigating aerosol hazards. A study is needed to investigate the relationship between aerosol combustion behaviors and the properties of the aerosols. This dissertation presents research on the combustion behaviors of flammable aerosols. Monodisperse aerosols created by industrial heat transfer fluids were generated using electrospray. The characteristics of flame propagations in aerosols and the influence of the presence of fuel droplets in the system are studied in the aerosol ignition tests. Flames in aerosols are characterized by non-uniform shapes and discrete flame fronts. Flames were observed in different burning modes. Droplet evaporation was found to play an important role in aerosol burning modes. Droplet evaporation behaviors and fuel vapor distributions are further related to aerosol droplet size, droplet spacing, movement velocity, and liquid volatility. The burning mode of a global flame with rapid size expansion is considered the most hazardous aerosol combustion scenario. This burning mode requires a smaller droplet size and smaller space between droplets. Larger droplet sizes and spacing may hinder the appearance of global flames. But when the liquid fuel has a certain level of volatility, there is an uneven distribution of fuel vapor in the system and this may cause the unique phenomenon of burning mode variations combined with enhanced flame propagation speed. Using an integrated model, the minimum ignition energy values of aerosols were predicted. The aerosol minimum ignition energy is influenced by the fuel-air equivalence ratio and the droplet size. Higher equivalence ratios, up to 1.0, significantly reduce the minimum ignition energy, while larger droplet sizes result in a higher minimum ignition energy.

Lian, Peng

2011-08-01T23:59:59.000Z

78

Infrared Thermography applied to measurement of Heat transfer coefficient of water in a pipe heated by Joule effect  

E-Print Network (OSTI)

. Internal sources of heat are due to convection from flow of the heat transfer fluid through the pipes. Heat (material, diameter, spacing, and burial depth), (4) system flow rates, (5) heat transfer fluid properties · heat transfer fluid = 42% propylene glycol @ a flow rate of 350 gpm · heat pump model = Water Furnace

79

Dispersed-Flow Film Boiling Heat Transfer Data near Spacer Grids in a Rod Bundle  

Science Conference Proceedings (OSTI)

Technical Paper / Radiation Effects and Their Relationship to Geological Repository / Heat Transfer and Fluid Flow

Graydon L. Yoder; Jr.; David G. Morris; Charles B. Mullins; Larry J. Ott

80

Heat transfer and fluid dynamics of air-water two-phase flow in micro-channels  

SciTech Connect

Heat transfer, pressure drop, and void fraction were simultaneously measured for upward heated air-water non-boiling two-phase flow in 0.51 mm ID tube to investigate thermo-hydro dynamic characteristics of two-phase flow in micro-channels. At low liquid superficial velocity j{sub l} frictional pressure drop agreed with Mishima-Hibiki's correlation, whereas agreed with Chisholm-Laird's correlation at relatively high j{sub l}. Void fraction was lower than the homogeneous model and conventional empirical correlations. To interpret the decrease of void fraction with decrease of tube diameter, a relation among the void fraction, pressure gradient and tube diameter was derived. Heat transfer coefficient fairly agreed with the data for 1.03 and 2.01 mm ID tubes when j{sub l} was relatively high. But it became lower than that for larger diameter tubes when j{sub l} was low. Analogy between heat transfer and frictional pressure drop was proved to hold roughly for the two-phase flow in micro-channel. But satisfactory relation was not obtained under the condition of low liquid superficial velocity. (author)

Kaji, Masuo; Sawai, Toru; Kagi, Yosuke [Department of Mechanical Engineering, School of Biology-Oriented Science and Technology, Kinki University, 930 Nishi-mitani, Kinokawa, Wakayama 649-6493 (Japan); Ueda, Tadanobu [Toyota Central R and D Laboratory, Incorporated, 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan)

2010-05-15T23:59:59.000Z

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


81

Handbook of heat and mass transfer. Volume 1  

Science Conference Proceedings (OSTI)

This two-volume series, the work of more than 100 contributors, presents advanced topics in industrial heat and mass transfer operations and reactor design technology. Volume 1 emphasizes heat transfer operations. The contents are: Fundamentsls of momentum and heat transfer. Scaling in laminar and turbulent heat and mass transfer. Heat flux in the Benar-Rayleigh problem. Hydrodynamics of free liquid jets and their influence on heat transfer. Natural convection heat transfer to power law fluids. Natural convection in evaporating droplets. Principles of heat and mass transfer with liquid evaporation. Bubble nucleation, growth, and departure in boiling heat transfer. Forced convection boiling in uniformly heated channels. Transient boiling heat transfer under forced convection. Prediction of heat transfer during forced convection subcooled boiling. Liquid metal heat transfer in turbulent pipe flows. Mixed convection in buoyant plumes. Nucleation and growth in the diffusion cloud chamber. Convective and radiative heat transfer of flowing gaseous-solid suspensions. Heat transfer in gas-solid fluidized beds. Gas convection and unsteady conduction in fluid bed heat transfer. Heat transfer between tubes and gas-solid fluid beds. Periodic heat transfer through inhomogeneous layers.

Cheremisinoff, N.P.

1986-01-01T23:59:59.000Z

82

Heat Transfer and Energy Diffusion Analysis of Cannula Ground Heat Exchanger  

Science Conference Proceedings (OSTI)

A heat transfer model about fluid flow and heat conduct in cannula ground heat exchanger were given in this article. The heat transfer characteristics were analyzed by means of numerical method of finite element. Affect of difference size of buried tubes ... Keywords: heat transfer, energy diffusion, ground heat exchanger, numerical method, couple mode

Jiang Yan; Gao Qing; Li Ming

2010-10-01T23:59:59.000Z

83

Nanofluid heat transfer enhancement for nuclear reactor applications  

E-Print Network (OSTI)

Colloidal dispersions of nanoparticles are known as `nanofluids'. Such engineered fluids offer the potential for enhancing heat transfer, particularly boiling heat transfer, while avoiding the drawbacks (i.e., erosion, ...

Buongiorno, Jacopo

84

Heat transfer and heat exchangers reference handbook  

Science Conference Proceedings (OSTI)

The purpose of this handbook is to provide Rocky Flats personnel with an understanding of the basic concepts of heat transfer and the operation of heat exchangers.

Not Available

1991-01-15T23:59:59.000Z

85

Microcellular Biomorphous Ceramics for Two Phase Heat Transfer ...  

Science Conference Proceedings (OSTI)

Heat transfer behavior of microcellular biomorphous Al2O3 was evaluated by a fluid-dynamic approach and tested in a planar capillary evaporator.

86

HEAT TRANSFER METHOD  

DOE Patents (OSTI)

A method is given for increasing burn-out heat fluxes under nucleate boiling conditions in heat exchanger tubes without incurring an increase in pumping power requirements. This increase is achieved by utilizing a spinning flow having a rotational velocity sufficient to produce a centrifugal acceleration of at least 10,000 g at the tube wall. At this acceleration the heat-transfer rate at burn out is nearly twice the rate which can be achieved in a similar tube utilizing axial flow at the same pumping power. At higher accelerations the improvement over axial flow is greater, and heat fluxes in excess of 50 x 10/sup 6/ Btu/hr/sq ft can be achieved.

Gambill, W.R.; Greene, N.D.

1960-08-30T23:59:59.000Z

87

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

E-Print Network (OSTI)

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

Kendall, Gail E.

1978-01-01T23:59:59.000Z

88

A Mountain-Scale Thermal Hydrologic Model for Simulating Fluid Flow and Heat Transfer in Unsaturated Fractured Rock  

E-Print Network (OSTI)

heat flow in porous media, heat pipe, reservoir simulation,and vapor often leads to “heat-pipe” conditions, the steadytwo-phase zone, is the heat-pipe (i.e. , a zone of constant

Wu, Yu-Shu; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, Gudmundur S.

2005-01-01T23:59:59.000Z

89

Thermal-Hydraulic Analyses of Heat Transfer Fluid Requirements and Characteristics for Coupling A Hydrogen Production Plant to a High-Temperature Nuclear Reactor  

DOE Green Energy (OSTI)

The Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the hightemperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power plant. An intermediate heat transport loop will be required to separate the operations and safety functions of the nuclear and hydrogen plants. A next generation high-temperature reactor could be envisioned as a single-purpose facility that produces hydrogen or a dual-purpose facility that produces hydrogen and electricity. Early plants, such as the proposed Next Generation Nuclear Plant, may be dual-purpose facilities that demonstrate both hydrogen and efficient electrical generation. Later plants could be single-purpose facilities. At this stage of development, both single- and dual-purpose facilities need to be understood. Seven possible configurations for a system that transfers heat between the nuclear reactor and the hydrogen and/or electrical generation plants were identified. These configurations included both direct and indirect cycles for the production of electricity. Both helium and liquid salts were considered as the working fluid in the intermediate heat transport loop. Methods were developed to perform thermalhydraulic and cycle-efficiency evaluations of the different configurations and coolants. The thermalhydraulic evaluations estimated the sizes of various components in the intermediate heat transport loop for the different configurations. The relative sizes of components provide a relative indication of the capital cost associated with the various configurations. Estimates of the overall cycle efficiency of the various configurations were also determined. The evaluations determined which configurations and coolants are the most promising from thermal-hydraulic and efficiency points of view. These evaluations also determined which configurations and options do not appear to be feasible at the current time.

C. B. Davis; C. H. Oh; R. B. Barner; D. F. Wilson

2005-06-01T23:59:59.000Z

90

A Mountain-Scale Thermal Hydrologic Model for Simulating Fluid Flow and Heat Transfer in Unsaturated Fractured Rock  

E-Print Network (OSTI)

grain-specific heat for each model grid layer, are providedand heat flow is simulated using the 3-D TH model grid (

Wu, Yu-Shu; Mukhopadhyay, Sumit; Zhang, Keni; Bodvarsson, Gudmundur S.

2005-01-01T23:59:59.000Z

91

HEAT TRANSFER DURING THE SHOCK-INDUCED IGNITION OF AN EXPOLSIVE GAS  

E-Print Network (OSTI)

11 Stagnation Point Heat Transfer Measurements in Air atR.M. , and Kemp, N.H. , Heat Transfer from High TemperatureProceedings of the 1963 Heat Transfer and Fluid Mechanics

Heperkan, H.

2013-01-01T23:59:59.000Z

92

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

Analysis of. Nonlinear Heat Transfer Problems." Report no.Berkeley, Ca. , APPENDIX A. HEAT TRANSFER BY CONDUCTION ANDMeeting, Technical Session on Heat Transfer in Nuclear Waste

Chan, T.

2010-01-01T23:59:59.000Z

93

Base fluid and temperature effects on the heat transfer characteristics of SiC in ethylene glycol/H2O and H2O nanofluids  

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

JOURNAL OF APPLIED PHYSICS 109, 014914 JOURNAL OF APPLIED PHYSICS 109, 014914 (2011) Base fluid and temperature effects on the heat transfer characteristics of SiC in ethylene glycol/H 2 O and H 2 O nanofluids Elena V. Timofeeva, 1,a) Wenhua Yu, 1 David M. France, 2 Dileep Singh, 3 and Jules L. Routbort 1 1 Energy Systems Division, Argonne National Laboratory, Argonne, Illinois 60439, USA 2 Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 842 W. Taylor St. (m/c 251), Chicago, Illinois 60607-7022, USA 3 Nuclear Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, USA (Received 27 July 2010; accepted 30 October 2010; published online 11 January 2011) Experimental data are presented for the thermal conductivity, viscosity, and turbulent flow

94

AN EXPERIMENTAL INVESTIGATION ON HEAT TRANSFER CHARACTERISTICS OF AIR AND CO2 IN MICROTUBES  

E-Print Network (OSTI)

by a cooling capacity, which is delivered in those rooms by heat exchangers where a heat transfer fluid - 2 and Fluid Science, 1-3:17. Mortada S., 2010. "Heat transfer performance of a mini-channel evaporator are mini-channel heat exchangers (MCHE) combining high heat transfer coefficients and low refrigerant

Kandlikar, Satish

95

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

standing of the heat transfer processes associated withto investigate the heat transfer and related processes in an

Chan, T.

2010-01-01T23:59:59.000Z

96

Frame Heat Transfer Research  

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

Developing Low-Conductance Window Frames: Capabilities and Developing Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools Arild Gustavsen 1,* , Dariush Arasteh 2 , Bjørn Petter Jelle 3,4 , Charlie Curcija 5 and Christian Kohler 2 1 Department of Architectural Design, History and Technology, Norwegian University of Science and Technology, Alfred Getz vei 3, NO-7491 Trondheim, Norway 2 Windows and Daylighting Group, Lawrence Berkeley National Laboratory, 1 Cyclotron Road Mail Stop 90R3111, Berkeley, CA 94720- 8134, USA 3 Department of Civil and Transport Engineering, Norwegian University of Science and Technology, Høgskoleringen 7A, NO-7491 Trondheim, Norway 4 Department of Building Materials and Structures, SINTEF Building and Infrastructure, Høgskoleringen 7B,NO-7465 Trondheim, Norway

97

Convective heat transfer in rotating, circular channels  

E-Print Network (OSTI)

Nusselt number values for flow in a rotating reference frame are obtained through computational fluid dynamic (CFD) analysis for Rossby numbers Ro ~1-4 and Reynolds numbers Re ~1,000-2,000. The heat-transfer model is first ...

Hogan, Brenna Elizabeth

2012-01-01T23:59:59.000Z

98

Halide and Oxy-Halide Eutectic Systems for High-Performance, High-Temperature Heat Transfer Fluids (Fact Sheet)  

DOE Green Energy (OSTI)

The University of Arizona, Arizona Statue University (ASU), and Georgia Institute of Technology 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.

Not Available

2012-12-01T23:59:59.000Z

99

Handbook of heat transfer fundamentals  

SciTech Connect

This handbook is on the fundamentals of heat transfer. It provides coverage on conduction, convection, and radiation and on thermophysical properties of materials.

Rohsenow, W.M.; Hartnett, J.P.; Ganic, E.N.

1985-01-01T23:59:59.000Z

100

Electrohydrodynamically enhanced condensation heat transfer.  

E-Print Network (OSTI)

??In a condenser the thickness of the liquid condensate film covering the cooled surface constitutes a resistance to the heat transfer. By establishing a non… (more)

Wawzyniak, Markus

2012-01-01T23:59:59.000Z

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


101

Fundamental heat transfer experiments of heat pipes for turbine cooling  

SciTech Connect

Fundamental heat transfer experiments were carried out for three kinds of heat pipes that may be applied to turbine cooling in future aero-engines. In the turbine cooling system with a heat pipe, heat transfer rate and start-up time of the heat pipe are the most important performance criteria to evaluate and compare with conventional cooling methods. Three heat pipes are considered, called heat pipe A, B, and C, respectively. All heat pipes have a stainless steel shell and nickel sintered powder metal wick. Sodium (Na) was the working fluid for heat pipes A and B; heat pipe C used eutectic sodium-potassium (NaK). Heat pipes B and C included noncondensible gas for rapid start-up. There were fins on the cooling section of heat pipes. In the experiments, an infrared image furnace supplied heat to the heat pipe simulating turbine blade surface conditions. In the results, heat pipe B demonstrated the highest heat flux of 17 to 20 W/cm{sup 2}. The start-up time was about 6 minutes for heat pipe B and about 6 minutes for heat pipe A. Thus, adding noncondensible gas effectively reduced start-up time. Although NaK is a liquid phase at room temperature, the start-up time of heat pipe C (about 7 to 8 minutes) was not shorter than the heat pipe B. The effect of a gravitational force on heat pipe performance was also estimated by inclining the heat pipe at an angle of 90 deg. There was no significant gravitational dependence on heat transport for heat pipes including noncondensible gas.

Yamawaki, S. [Ishikawajima-Harima Heavy Industries Co., Ltd., Tokyo (Japan); Yoshida, T.; Taki, M.; Mimura, F. [National Aerospace Lab., Tokyo (Japan)

1998-07-01T23:59:59.000Z

102

An experimental investigation of convection heat transfer to supercritical carbon dioxide in miniature tubes  

E-Print Network (OSTI)

-year research program in heat transfer and viscoelastic fluid flows, after working for some time in industry of All Sciences), Fluid Mechanics, Heat Transfer and related fluid-thermal-energy sciences; with emphases Press series Advances in Heat Transfer, Volume 19, and "Viscosity" in CRC Press' Measurement

Zhao, Tianshou

103

Urban Sewage Delivery Heat Transfer System (2): Heat Transfer  

E-Print Network (OSTI)

The thimble delivery heat-transfer (TDHT) system is one of the primary modes to utilize the energy of urban sewage. Using the efficiency-number of transfer units method ( ), the heat-transfer efficiencies of the parallel-flow and reverse-flow TDTH forms are analyzed and the calculation formulas and characteristic are also given. The results indicate that the efficiency of the parallel-flow form is greater than that of the reverse-flow, so the TDTH system must choose the parallel-flow form. The distance-load ratio (DLR) is defined and the minimum DLR is obtained by the technical and economic feasibility analysis. The paper will provide references for heat-transfer calculation and schematic determination of urban sewage cool or heat source applied delivery heat transfer methods.

Zhang, C.; Wu, R.; Li, X.; Li, G.; Zhuang, Z.; Sun, D.

2006-01-01T23:59:59.000Z

104

Heat pump/refrigerator using liquid working fluid  

DOE Patents (OSTI)

A heat transfer device is described that can be operated as a heat pump or refrigerator, which utilizes a working fluid that is continuously in a liquid state and which has a high temperature-coefficient of expansion near room temperature, to provide a compact and high efficiency heat transfer device for relatively small temperature differences as are encountered in heating or cooling rooms or the like. The heat transfer device includes a pair of heat exchangers that may be coupled respectively to the outdoor and indoor environments, a regenerator connecting the two heat exchangers, a displacer that can move the liquid working fluid through the heat exchangers via the regenerator, and a means for alternately increasing and decreasing the pressure of the working fluid. The liquid working fluid enables efficient heat transfer in a compact unit, and leads to an explosion-proof smooth and quiet machine characteristic of hydraulics. The device enables efficient heat transfer as the indoor-outdoor temperature difference approaches zero, and enables simple conversion from heat pumping to refrigeration as by merely reversing the direction of a motor that powers the device.

Wheatley, John C. (Del Mar, CA); Paulson, Douglas N. (Del Mar, CA); Allen, Paul C. (Solana Beach, CA); Knight, William R. (Corvallis, OR); Warkentin, Paul A. (San Diego, CA)

1982-01-01T23:59:59.000Z

105

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

E-Print Network (OSTI)

22]. Fluid flow and heat-transfer processes in a two-phase,processes associated with multiphase flow and heat transferprocesses has also motivated development of fluid flow and heat transfer

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

2006-01-01T23:59:59.000Z

106

Investigation of the pool boiling heat transfer enhancement of nano-engineered fluids by means of high-speed infrared thermography  

E-Print Network (OSTI)

A high-speed video and infrared thermography based technique has been used to obtain detailed and fundamental time- and space-resolved information on pool boiling heat transfer. The work is enabled by recent advances in ...

Gerardi, Craig Douglas

2009-01-01T23:59:59.000Z

107

Modeling of Heat Transfer in Geothermal Heat Exchangers  

E-Print Network (OSTI)

Ground-coupled heat pump (GCHP) systems have been gaining increasing popularity for space conditioning in residential and commercial buildings. The geothermal heat exchanger (GHE) is devised for extraction or injection of thermal energy from/into the ground. This paper summarizes the authors' studies on heat transfer in ground-coupled heat pump systems. Taking the fluid axial convective heat transfer and thermal “short-circuiting” among U-tube legs into account, a quasi-3-D model has been solved for heat transfer inside boreholes. The transient 2-D temperature response in a semi-infinite medium with a line-source of finite length has also been derived for heat conduction outside boreholes. In order to investigate the impact of groundwater advection on the performance of ground heat exchangers, an analytical solution is obtained for a line heat source in an infinite porous medium with groundwater advection. These explicit expressions have more solid theoretical basis, and can be easily incorporated into computer programs for thermal analysis and engineering design of ground heat exchangers.

Cui, P.; Man, Y.; Fang, Z.

2006-01-01T23:59:59.000Z

108

Testing thermocline filler materials and molten-salt heat transfer fluids for thermal energy storage systems used in parabolic trough solar power plants.  

DOE Green Energy (OSTI)

Parabolic trough power systems that utilize concentrated solar energy to generate electricity are a proven technology. Industry and laboratory research efforts are now focusing on integration of thermal energy storage as a viable means to enhance dispatchability of concentrated solar energy. One option to significantly reduce costs is to use thermocline storage systems, low-cost filler materials as the primary thermal storage medium, and molten nitrate salts as the direct heat transfer fluid. Prior thermocline evaluations and thermal cycling tests at the Sandia National Laboratories' National Solar Thermal Test Facility identified quartzite rock and silica sand as potential filler materials. An expanded series of isothermal and thermal cycling experiments were planned and implemented to extend those studies in order to demonstrate the durability of these filler materials in molten nitrate salts over a range of operating temperatures for extended timeframes. Upon test completion, careful analyses of filler material samples, as well as the molten salt, were conducted to assess long-term durability and degradation mechanisms in these test conditions. Analysis results demonstrate that the quartzite rock and silica sand appear able to withstand the molten salt environment quite well. No significant deterioration that would impact the performance or operability of a thermocline thermal energy storage system was evident. Therefore, additional studies of the thermocline concept can continue armed with confidence that appropriate filler materials have been identified for the intended application.

Kelly, Michael James; Hlava, Paul Frank; Brosseau, Douglas A.

2004-07-01T23:59:59.000Z

109

HEAT TRANSFER MEANS  

DOE Patents (OSTI)

A heat exchanger is adapted to unifomly cool a spherical surface. Equations for the design of a spherical heat exchanger hav~g tubes with a uniform center-to-center spining are given. The heat exchanger is illustrated in connection with a liquid-fueled reactor.

Fraas, A.P.; Wislicenus, G.F.

1961-07-11T23:59:59.000Z

110

SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer  

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

High Operating Temperature Liquid High Operating Temperature Liquid Metal Heat Transfer Fluids to someone by E-mail Share SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Facebook Tweet about SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Twitter Bookmark SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Google Bookmark SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Delicious Rank SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Digg Find More places to share SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards

111

Devices with extended area structures for mass transfer processing of fluids  

DOE Patents (OSTI)

A microchannel device includes several mass transfer microchannels to receive a fluid media for processing at least one heat transfer microchannel in fluid communication with a heat transfer fluid defined by a thermally conductive wall, and at several thermally conductive fins each connected to the wall and extending therefrom to separate the mass transfer microchannels from one another. In one form, the device may optionally include another heat transfer microchannel and corresponding wall that is positioned opposite the first wall and has the fins and the mass transfer microchannels extending therebetween.

TeGrotenhuis, Ward E. (Kennewick, WA); Wegeng, Robert S. (Richland, WA); Whyatt, Greg A. (West Richland, WA); King, David L. (Richland, WA); Brooks, Kriston P. (Kennewick, WA); Stenkamp, Victoria S. (Richland, WA)

2009-04-21T23:59:59.000Z

112

Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump  

DOE Patents (OSTI)

Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use, as the heat transfer medium, the working fluid of the absorption system taken from the generator at a location where the working fluid has a rich liquor concentration.

Phillips, Benjamin A. (Benton Harbor, MI); Zawacki, Thomas S. (St. Joseph, MI)

1998-07-21T23:59:59.000Z

113

Heat and moisture transfer through clothing  

E-Print Network (OSTI)

R. C. Eberhart (ed), Heat transfer in medicine and biology.Convective and radiative heat transfer coefficients for2008. Study of heat and moisture transfer within multi-layer

Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie

2009-01-01T23:59:59.000Z

114

Controlling the Heat Transfer  

Science Conference Proceedings (OSTI)

Through experimental validation that air conduction is shown to be typically the dominant thermal transport mechanism in the contact region, the heat conduction

115

Fluid bed material transfer method  

DOE Patents (OSTI)

A fluidized bed apparatus comprising a pair of separated fluid bed enclosures, each enclosing a fluid bed carried on an air distributor plate supplied with fluidizing air from below the plate. At least one equalizing duct extending through sidewalls of both fluid bed enclosures and flexibly engaged therewith to communicate the fluid beds with each other. The equalizing duct being surrounded by insulation which is in turn encased by an outer duct having expansion means and being fixed between the sidewalls of the fluid bed enclosures.

Pinske, Jr., Edward E. (Akron, OH)

1994-01-01T23:59:59.000Z

116

Comparison of heat transfer in solar collectors with heat pipe versus flow through absorbers  

DOE Green Energy (OSTI)

Analysis of heat transfer in solar collectors with heat pipe absorbers is compared to that for collectors with flow through absorbers. Both pumped and thermosiphon systems that produce hot water or other heated fluids are discussed. In these applications the heat pipe absorber suffers a heat transfer penalty compared with the flow through absorber, but in many cases the penalty can be minimized by proper design at the heat pipe condenser and system manifold. When the solar collector is used to drive an absorption chiller, the heat pipe absorber has better heat transfer characteristics than the flow through absorber.

Hull, J.R.

1985-01-01T23:59:59.000Z

117

Heat Transfer Enhancement in Thermoelectric Power Generation.  

E-Print Network (OSTI)

??Heat transfer plays an important role in thermoelectric (TE) power generation because the higher the heat-transfer rate from the hot to the cold side of… (more)

Hu, Shih-yung

2009-01-01T23:59:59.000Z

118

Numerical study of 2D heat transfer in a scraped surface heat exchanger  

E-Print Network (OSTI)

Numerical study of 2D heat transfer in a scraped surface heat exchanger K.-H. Sun a,*, D.L. Pyle heat exchanger with non- Newtonian power law fluids is undertaken. Numerical results are generated of scraped surface heat exchanger design are assessed in the light of the results. Ã? 2003 Elsevier Ltd. All

119

Microchannel crossflow fluid heat exchanger and method for its fabrication  

DOE Patents (OSTI)

A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance.

Swift, Gregory W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM); Wheatley, John C. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

120

Microchannel crossflow fluid heat exchanger and method for its fabrication  

DOE Patents (OSTI)

A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance.

Swift, G.W.; Migliori, A.; Wheatley, J.C.

1982-08-31T23:59:59.000Z

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


121

Microchannel crossflow fluid heat exchanger and method for its fabrication  

DOE Patents (OSTI)

A microchannel crossflow fluid heat exchanger and a method for its fabrication are disclosed. The heat exchanger is formed from a stack of thin metal sheets which are bonded together. The stack consists of alternating slotted and unslotted sheets. Each of the slotted sheets includes multiple parallel slots which form fluid flow channels when sandwiched between the unslotted sheets. Successive slotted sheets in the stack are rotated ninety degrees with respect to one another so as to form two sets of orthogonally extending fluid flow channels which are arranged in a crossflow configuration. The heat exchanger has a high surface to volume ratio, a small dead volume, a high heat transfer coefficient, and is suitable for use with fluids under high pressures. The heat exchanger has particular application in a Stirling engine that utilizes a liquid as the working substance. 9 figs.

Swift, G.W.; Migliori, A.; Wheatley, J.C.

1985-05-14T23:59:59.000Z

122

Heat transfer characteristics of a three-phase volume boiling direct contact heat exchanger  

DOE Green Energy (OSTI)

The advantages of direct contact heat transfer over heat transfer utilizing conventional metallic heat exchangers are listed. The performance characteristics of a three-phase direct contact heat exchanger in near counterflow operation were evaluated using water as the continuous phase fluid and refrigerant 113 as the dispersed phase fluid. Conclusions are drawn from the results having to do with refrigerant injection technique, vessel operating height, mass flow rate of refrigerant, water inlet temperature, operation at pinch point temperature differences below 13 to 20/sup 0/C, and operation with a dispersed phase fluid less dense than water. (MHR)

Blair, C.K.; Boehm, R.F.; Jacobs, H.R.

1976-03-01T23:59:59.000Z

123

Nanoscale heat transfer - from computation to experiment  

E-Print Network (OSTI)

Heat transfer can differ distinctly at the nanoscale from that at the macroscale. Recent advancement in

Luo, Tengfei

2013-04-09T23:59:59.000Z

124

Heat Transfer Technology  

E-Print Network (OSTI)

Almost every industrial process needs some form of cooling. Water is still the most extensively used fluid for cooling, but the days when plenty of it was available are gone forever. Water conservation is currently achieved by the use of evaporative cooling, more commonly known as 'Cooling Tower'. The logo of the Cooling Tower Institute reads 'It Is Good Business to Conserve Water' but today it is not good enough. In many areas water to compensate for Wet Cooling Tower evaporation losses cannot be economically found and better solutions are needed. The paper explores potential improvements in Wet Cooling Tower design and operation as well as new WET DRY tower combinations in order to conserve even more water.

Lefevre, M. R.

1984-01-01T23:59:59.000Z

125

A unified numerical framework model for simulating flow, transport, and heat transfer in porous and fractured media  

E-Print Network (OSTI)

fluid flow, multicomponent transport, and heat transfer in porous and fractured media,fluid flow, solute transport, and heat transfer occur in porous and fractured media.fluid flow, mass transport, and heat-transfer processes through porous and fractured media.

Wu, Yu-Shu

2004-01-01T23:59:59.000Z

126

Heat transfer in freeboard region of fluidized beds  

SciTech Connect

This research involved the study of heat transfer and fluid mechanic characteristics around a horizontal tube in the freeboard region of fluidized beds. Heat transfer coefficients were experimetnally measured for different bed temperatures, particle sizes, gas flow rates, and tube elevations in the freeboard region of air fluidized beds at atmospheric pressure. Local heat transfer coefficients were found to vary significantly with angular position around the tube. Average heat transfer coefficients were found to decrease with increasing freeboard tube elevation and approach the values for gas convection plus radiation for any given gas velocity. For a fixed tube elevation, heat transfer coefficients generally increased with increasing gas velocity and with high particle entrainment they can approach the magnitudes found for immersed tubes. Heat transfer coefficients were also found to increase with increasing bed temperature. It was concluded that this increase is partly due to increase of radiative heat transfer and partly due to change of thermal properties of the fluidizing gas and particles. To investigate the fluid mechanic behavior of gas and particles around a freeboard tube, transient particle tube contacts were measured with a special capacitance probe in room temperature experiments. The results indicated that the tube surface experiences alternating dense and lean phase contacts. Quantitative information for local characteristics was obtained from the capacitance signals and used to develop a phenomenological model for prediction of the heat transfer coefficients around freeboard tubes. The packet renewal theory was modified to account for the dense phase heat transfer and a new model was suggested for the lean phase heat transfer. Finally, an empirical freeboard heat transfer correlation was developed from functional analysis of the freeboard heat transfer data using nondimensional groups representing gas velocity and tube elevation.

Biyikli, S.; Tuzla, K.; Chen, J.C.

1983-10-01T23:59:59.000Z

127

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

law of similitude for linear heat conduction was utilized tothe analogy between heat conduction and fluid flow in por­the effects of heat conduction through the vermiculite heat

Chan, T.

2010-01-01T23:59:59.000Z

128

Heat Transfer of a Multiple Helical Coil Heat Exchanger Using a Microencapsulated Phase Change Material Slurry  

E-Print Network (OSTI)

The present study has focused on the use of coil heat exchangers (CHEs) with microencapsulated phase change material (MPCM) slurries to understand if CHEs can yield greater rates of heat transfer. An experimental study was conducted using a counterflow CHE consisting of 3 helical coils. Two separate tests were conducted, one where water was used as heat transfer fluid (HTF) on the coil and shell sides, respectively; while the second one made use of MPCM slurry and water on the coil and shell sides, respectively. The NTU-effectiveness relationship of the CHE when MPCM fluid is used approaches that of a heat exchanger with a heat capacity ratio of zero. The heat transfer results have shown that when using a MPCM slurry, an increase in heat transfer rate can be obtained when compared to heat transfer results obtained using straight heat transfer sections. It has been concluded that the increased specific heat of the slurry as well as the fluid dynamics in helical coil pipes are the main contributors to the increased heat transfer.

Gaskill, Travis

2011-12-01T23:59:59.000Z

129

Evaluation of fluid bed heat exchanger optimization parameters. Final report  

SciTech Connect

Uncertainty in the relationship of specific bed material properties to gas-side heat transfer in fluidized beds has inhibited the search for optimum bed materials and has led to over-conservative assumptions in the design of fluid bed heat exchangers. An experimental program was carried out to isolate the effects of particle density, thermal conductivity, and heat capacitance upon fluid bed heat transfer. A total of 31 tests were run with 18 different bed material loads on 12 material types; particle size variations were tested on several material types. The conceptual design of a fluidized bed evaporator unit was completed for a diesel exhaust heat recovery system. The evaporator heat transfer surface area was substantially reduced while the physical dimensions of the unit increased. Despite the overall increase in unit size, the overall cost was reduced. A study of relative economics associated with bed material selection was conducted. For the fluidized bed evaporator, it was found that zircon sand was the best choice among materials tested in this program, and that the selection of bed material substantially influences the overall system costs. The optimized fluid bed heat exchanger has an estimated cost 19% below a fin augmented tubular heat exchanger; 31% below a commercial design fluid bed heat exchanger; and 50% below a conventional plain tube heat exchanger. The comparisons being made for a 9.6 x 10/sup 6/ Btu/h waste heat boiler. The fluidized bed approach potentially has other advantages such as resistance to fouling. It is recommended that a study be conducted to develop a systematic selection of bed materials for fluidized bed heat exchanger applications, based upon findings of the study reported herein.

Not Available

1980-03-01T23:59:59.000Z

130

International Communications in Heat and Mass Transfer, volume 39, issue 10, December 2012, Pages 15191521.  

E-Print Network (OSTI)

.P. Hodson, T.J. Lu, Fluid-flow and endwall heat-transfer characteristics of an ultralight lattice and water as the working fluid. Thermodynamic design principles for a multifunctional heat pipe sandwich.P. Hodson, D.T. Queheillalt, D.J. Sypeck, H.N.G. Wadley, The effects of topology upon fluid-flow and heat

Cambridge, University of

131

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

Open Energy Info (EERE)

Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas- Features And Examples Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Heat Flow,...

132

Available Technologies: Heat Transfer Interface for Thermo ...  

Refrigeration systems; Internal combustion engines; ... The components of the technology could be used to improve heat transfer in industrial, ...

133

Heat Transfer & Alternative Energy Systems Group Staff ...  

Science Conference Proceedings (OSTI)

Heat Transfer and Alternative Energy Systems Group Staff. Staff Listing. Dr. William M. Healy, Leader, Supervisory Mechanical ...

2013-08-07T23:59:59.000Z

134

Acoustically Enhanced Boiling Heat Transfer  

E-Print Network (OSTI)

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

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

2008-01-07T23:59:59.000Z

135

Numerical investigation of heat transfer enhancement by carbon nano fibers deposited on a flat plate  

Science Conference Proceedings (OSTI)

Numerical simulations of flow and heat transfer have been performed for flow over a plate surface covered with carbon nano fibers (CNFs). The CNFs influence on fluid flow and heat transfer has been investigated. Firstly, a stochastic model for CNFs deposition ... Keywords: Carbon nano fibers, Heat transfer, Lattice Boltzmann method

Nikola Pelevic; Theo Van Der Meer

2013-03-01T23:59:59.000Z

136

Handbook of numerical heat transfer  

Science Conference Proceedings (OSTI)

A comprehensive presentation is given of virtually all numerical methods that are suitable for the analysis of the various heat transverse and fluid flow problems that occur in research, practice, and university instruction. After reviewing basic methodologies, the following topics are covered: finite difference and finite element methods for parabolic, elliptic, and hyperbolic systems; a comparative appraisal of finite difference versus finite element methods; integral and integrodifferential systems; perturbation methods; Monte Carlo methods; finite analytic methods; moving boundary problems; inverse problems; graphical display methods; grid generation methods; and programing methods for supercomputers.

Minkowycz, W.J.; Sparrow, E.M.; Schneider, G.E.; Pletcher, R.H.

1988-01-01T23:59:59.000Z

137

Heat transfer via dropwise condensation on hydrophobic microstructured surfaces  

E-Print Network (OSTI)

Dropwise condensation has the potential to greatly increase heat transfer rates. Heat transfer coefficients by dropwise condensation and film condensation on microstructured silicon chips were compared. Heat transfer ...

Ruleman, Karlen E. (Karlen Elizabeth)

2009-01-01T23:59:59.000Z

138

Control system for fluid heated steam generator  

DOE Patents (OSTI)

A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

Boland, James F. (Bonneville County, ID); Koenig, John F. (Idaho Falls, ID)

1985-01-01T23:59:59.000Z

139

Control system for fluid heated steam generator  

DOE Patents (OSTI)

A control system for controlling the location of the nucleate-boiling region in a fluid heated steam generator comprises means for measuring the temperature gradient (change in temperature per unit length) of the heating fluid along the steam generator; means for determining a control variable in accordance with a predetermined function of temperature gradients and for generating a control signal in response thereto; and means for adjusting the feedwater flow rate in accordance with the control signal.

Boland, J.F.; Koenig, J.F.

1984-05-29T23:59:59.000Z

140

Heat exchanger device and method for heat removal or transfer  

Science Conference Proceedings (OSTI)

Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a heat conducting structure, across a narrow air gap, to a rotating heat transfer structure immersed in a surrounding medium such as air.

Koplow, Jeffrey P. (San Ramon, CA)

2012-07-24T23:59:59.000Z

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


141

TURBULENT EXCHANGE OF MOMENTUM, MASS, AND HEAT BETWEEN FLUID STREAMS AND PIPE WALL  

SciTech Connect

S>A new correlation is presented to describe mass and heat transfer to a fluid in a fully developed turbulent flow in a pipe. The correlation differs from earlier empirical relations in that it is based on a theoretical continuous eddy-viscosity distribution from the wall to the center of the pipe. Transfer rates calculated from the new correlation are in excellent agree ment with experimental data on mass and heat transfer to fluid streams. (auth)

Wasan, D.T.; Wilke, C.R.

1963-03-01T23:59:59.000Z

142

Numerical and experimental validation of heat and mass transfer during heat treatment of wood  

Science Conference Proceedings (OSTI)

In the current work, the three-dimensional Navier-Stokes equations along with the energy and concentration equations for the fluid coupled with the energy and mass conservation equations for the solid (wood) are solved to study the transient heat and ... Keywords: Luikov's model, conjugate problem, heat and mass transfer, high-temperature wood treatment, mathematical modeling, validation

R. Younsi; D. Kocaefe; S. Poncsak; T. Junjun

2007-05-01T23:59:59.000Z

143

Investigation of methods to transfer heat from solar liquid-heating collectors to heat storage tanks. Final report  

DOE Green Energy (OSTI)

A study was made of the methods available to transfer heat from the collector to the water storage tank in water heating systems. In counterflow heat exchangers used in double loop water heating systems, it was found to be more important to use a high water flowrate than a high heat transfer fluid flowrate. It was earlier thought to be best to have matched WC/sub p/ (mass flowrate-specific heat) products in the loops. It was shown in this study that the water WC/sub p/ product should be about twice as large as that of the heat transfer fluid. It was found that neither the heat exchanger type nor the size was very critical, so that very simple criteria were adequate in determining optimum heat exchanger size. It was found that there is a definite system size below which one should use a traced tank or a coil in a tank. Equations and optimization criteria were developed for traced tanks or tanks with coils. At present, there is no quantitative understanding of liquid to liquid (direct contact) heat exchangers, though they are clearly quite effective. Draindown systems are discussed, and several appendices are included on heat transfer and other characteristics of fluid and of equipment.

Horel, J. D.; de Winter, F.

1978-04-20T23:59:59.000Z

144

Heat transfer pathways in underfloor air distribution (UFAD) systems  

E-Print Network (OSTI)

the following heat transfer processes: conduction throughtudes of the major heat transfer processes in a typical room

Bauman, F.; Jin, H.; Webster, T.

2006-01-01T23:59:59.000Z

145

Optical properties of a solar-absorbing molten salt heat transfer fluid. [Eutectic mixture of KNO3, NaNO2, and NaNO3 with particle suspensions of cobalt oxides or copper oxides  

DOE Green Energy (OSTI)

The optical absorption properties of a high temperature molten salt heat transfer fluid were measured from 0.35 ..mu..m to 2.5 ..mu..m using both hemispherical transmission and reflection techniques. This fluid has application as a direct-absorbing working fluid in a high temperature central receiver solar energy facility. The absorption spectrum of the pure molten fluid--a eutectic mixture of KNO/sub 3/, NaNO/sub 2/, and NaNO/sub 3/, known as Hitec (Du Pont trade name)--displays a fundamental absorption edge near 410 nm, which was found to shift to longer wavelength linearly with temperature. Throughout the remainder of the visible spectrum, the fluid is transparent. To enhance its solar absorption, particulate metallic oxides of Co or Cu were introduced into the fluid. Absorption spectra of these oxide particle suspensions in the molten salt were determined as a function of dopant concentration ranging from 0 to 0.1 wt% metal nitrate added to the Hitec. These measurements were carried out at 200/sup 0/C under flow conditions to cause a homogeneous suspension of particles. Special transmission and reflection flow cells were designed and constructed to handle 200/sup 0/C fluids. The suspended particles cause an additional optical absorption throughout the visible spectrum which is characteristic of the particular metallic oxide and closely follows a Beer-Lambert concentration dependence. The solar averaged absorption in a fixed layer thickness was calculated for various concentrations of the fluid-oxide mixtures. The fluid without oxide particles absorbs approximately 8% of the solar spectrum per cm of path length. Addition of 0.1 wt% of Co(NO/sub 3/)/sub 2/.6H/sub 2/O increases this absorption to approximately 90% per cm. Of the oxides studied, Co/sub 3/O/sub 4/ particle suspensions offer better solar absorption characteristics than CuO. Effects of particulate scattering on the measurements are discussed.

Drotning, W.D.

1977-06-01T23:59:59.000Z

146

Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas-  

Open Energy Info (EERE)

Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas- Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas- Features And Examples Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Heat Flow, Heat Transfer And Lithosphere Rheology In Geothermal Areas- Features And Examples Details Activities (5) Areas (5) Regions (0) Abstract: Surface heat flow measurements over active geothermal systems indicate strongly positive thermal anomalies. Whereas in "normal" geothermal settings, the surface heat flow is usually below 100-120 mW m- 2, in active geothermal areas heat flow values as high as several watts per meter squared can be found. Systematic interpretation of heat flow patterns sheds light on heat transfer mechanisms at depth on different lateral, depth and time scales. Borehole temperature profiles in active geothermal

147

Enhanced heat transfer for thermionic power modules  

DOE Green Energy (OSTI)

The thermionic power module is capable of operating at very high heat fluxes, which in turn serve to reduce capital costs. The most efficient operation also requires uniform heat fluxes. The development of enhanced heat transfer systems is required to meet the demand for high heat fluxes (>20 w/cm/sup 2/) at high temperatures (>1500K) which advanced thermionic power modules place upon combustion systems. Energy transfer from the hot combustion gases may take place by convection, radiation, or a combination of radiation and convection. Enhanced convective heat transfer with a jet impingement system has been demonstrated in a thermionic converter. The recently-developed cellular ceramic radiative heat transfer system has also been applied to a thermionic converter. By comparing the jet impingement and cellular ceramic radiative heat transfer systems, an appropriate system may be selected for utilization in advanced thermionic power modules. Results are reported.

Johnson, D.C.

1981-07-01T23:59:59.000Z

148

Heat Transfer In Turbine Mid Structures.  

E-Print Network (OSTI)

??In order to estimate the life time of a cooled gas turbine component, knowledge of the heat transfer is essential in order to predict the… (more)

Abou-Taouk, Abdallah

2006-01-01T23:59:59.000Z

149

Enhanced Heat Transfer in Composite Materials.  

E-Print Network (OSTI)

??Many composite materials are composed of a matrix reinforced with fibers. Carbon fiber composites are currently being used for high heat transfer applications. Carbon fibers… (more)

Pathak, Sayali V.

2013-01-01T23:59:59.000Z

150

Interface Heat Transfer Effects for Solidification Processes  

Science Conference Proceedings (OSTI)

The solidification rate of a casting is governed by the rate of heat extraction, which in turn is dominated by the rate of heat transfer across the casting-mold ...

151

Modeling of fluid and heat flow in fractured geothermal reservoirs  

DOE Green Energy (OSTI)

In most geothermal reservoirs large-scale permeability is dominated by fractures, while most of the heat and fluid reserves are stored in the rock matrix. Early-time fluid production comes mostly from the readily accessible fracture volume, while reservoir behavior at later time depends upon the ease with which fluid and heat can be transferred from the rock matrix to the fractures. Methods for modeling flow in fractured porous media must be able to deal with this matrix-fracture exchange, the so-called interporosity flow. This paper reviews recent work at Lawrence Berkeley Laboratory on numerical modeling of nonisothermal multiphase flow in fractured porous media. We also give a brief summary of simulation applications to problems in geothermal production and reinjection. 29 refs., 1 fig.

Pruess, K.

1988-08-01T23:59:59.000Z

152

HEAT EXCHANGER DEVICE AND METHOD FOR HEAT REMOVAL OR TRANSFER ...  

Systems and methods for a forced-convection heat exchanger are provided. In one embodiment, heat is transferred to or from a thermal load in thermal contact with a ...

153

Heat Transfer Characteristics of a Generalized Divided Flow Heat Exchanger  

E-Print Network (OSTI)

The concept of a "Divided-flow" heat exchanger is generalized by locating the shell inlet (or outlet) nozzle off-center such that the two shell sub-streams are unequal and traverse unequal flow paths. The governing equations for heat transfer in such an exchanger are derived and solved leading to an optimization problem. In this problem, the optimal subdivision of heat transfer surface to minimize required overall heat transfer surface, under certain restricted conditions, is sought. It is shown that the off-center nozzle location can be selected judiciously so as to maintain (or even improve heat transfer) while reducing the gross shellside pressure loss. Thus, the pumping costs are minimized without sacrificing heat transfer.

Singh, K. P.

1979-01-01T23:59:59.000Z

154

Curvature dependence of the interfacial heat and mass transfer coefficients  

E-Print Network (OSTI)

Nucleation is often accompanied by heat transfer between the surroundings and a nucleus of a new phase. The interface between two phases gives an additional resistance to this transfer. For small nuclei the interfacial curvature is high, which affects not only equilibrium quantities such as surface tension, but also the transport properties. In particular, high curvature affects the interfacial resistance to heat and mass transfer. We develop a framework for determining the curvature dependence of the interfacial heat and mass transfer resistances. We determine the interfacial resistances as a function of a curvature. The analysis is performed for a bubble of a one-component fluid and may be extended to various nuclei of multicomponent systems. The curvature dependence of the interfacial resistances is important in modeling transport processes in multiphase systems.

K. S. Glavatskiy; D. Bedeaux

2013-10-11T23:59:59.000Z

155

Containment condensing heat transfer. [PWR; BWR  

SciTech Connect

This report presents a mechanistic heat-transfer model that is valid for large scale containment heat sinks. The model development is based on the determination that the condensation is controlled by mass diffusion through the vapor-air boundary layer, and the application of the classic Reynolds' analogy to formulate expressions for the transfer of heat and mass based on hydrodynamic measurements of the momentum transfer. As a result, the analysis depends on the quantification of the shear stress (momentum transfer) at the interface between the condensate film and the vapor-air boundary layer. In addition, the currently used Tagami and Uchida test observations and their range of applicability are explained.

Gido, R.G.; Koestel, A.

1983-01-01T23:59:59.000Z

156

Radiative heat transfer between dielectric bodies  

E-Print Network (OSTI)

The recent development of a scanning thermal microscope (SThM) has led to measurements of radiative heat transfer between a heated sensor and a cooled sample down to the nanometer range. This allows for comparision of the known theoretical description of radiative heat transfer, which is based on fluctuating electrodynamics, with experiment. The theory itself is a macroscopic theory, which can be expected to break down at distances much smaller than 10-8m. Against this background it seems to be reasonable to revisit the known macroscopic theory of fluctuating electrodynamics and of radiative heat transfer.

Svend-Age Biehs

2011-03-16T23:59:59.000Z

157

Steady-state heat transfer in an inverted U-tube steam generator  

SciTech Connect

Experimental results are presented involving U-tube steam generator tube bundle local heat transfer and fluid conditions during steady-state, full-power operations performed at high temperatures and pressures with conditions typical of a pressurized water reactor (15.0 MPa primary pressure, 600 K hot-leg fluid temperatures, 6.2 MPa secondary pressure). The MOD-2C facility represents the state-of-the-art in measurement of tube local heat transfer data and average tube bundle secondary fluid density at several elevations, which allows an estimate of the axial heat transfer and void distributions during steady-state and transient operations. The method of heat transfer data reduction is presented and the heat flux, secondary convective heat transfer coefficient, and void fraction distributions are quantified for steady-state, full-power operations.

Boucher, T.J.

1986-01-01T23:59:59.000Z

158

Steady-state heat transfer in an inverted U-tube steam generator  

Science Conference Proceedings (OSTI)

Experimental results are presented involving U-tube steam generator tube bundle local heat transfer and fluid conditions during stead-state, full-power operations performed at high temperatures and pressures with conditions typical of a pressurized water reactor (15.0 MPa primary pressure, 600 K steam generator inlet plenum fluid temperatures, 6.2 MPa secondary pressure). The Semiscale (MOD-2C facility represents the state-of-the-art in measurement of tube local heat transfer data and average tube bundle secondary fluid density at several elevations, which allows an estimate of the axial heat transfer and void distributions during steady-state and transient operations. The method of heat transfer data reduction is presented and the heat flux, secondary convective heat transfer coefficient, and void fraction distributions are quantified for steady-state, full-power operations.

Boucher, T.J.

1987-01-01T23:59:59.000Z

159

Heat Transfer Enhancement: Second Generation Technology  

E-Print Network (OSTI)

This paper reviews current activity in the field of enhanced heat transfer, with the aim of illustrating the technology and typical applications. Guidelines for application of enhanced surfaces are given, and practical concerns and economics are discussed. Special attention is directed toward use of enhanced surfaces in industrial process heat exchangers and heat recovery equipment.

Bergles, A. E.; Webb, R. L.

1984-01-01T23:59:59.000Z

160

Dynamics of heat transfer between nano systems  

E-Print Network (OSTI)

We develop a dynamical theory of heat transfer between two nano systems. In particular, we consider the resonant heat transfer between two nanoparticles due to the coupling of localized surface modes having a finite spectral width. We model the coupled nanosystem by two coupled quantum mechanical oscillators, each interacting with its own heat bath, and obtain a master equation for the dynamics of heat transfer. The damping rates in the master equation are related to the lifetimes of localized plasmons in the nanoparticles. We study the dynamics towards the steady state and establish connection with the standard theory of heat transfer in steady state. For strongly coupled nano particles we predict Rabi oscillations in the mean occupation number of surface plasmons in each nano particle.

Svend-Age Biehs; Girish S. Agarwal

2012-10-18T23:59:59.000Z

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


161

Property Libraries for Working Fluids for Calculating Heat ...  

Science Conference Proceedings (OSTI)

... properties of working fluids can be used for the daily work of an engineer who calculates heat cycles, steam or gas turbines, boilers, heat pumps or ...

2006-07-20T23:59:59.000Z

162

Passive heat transfer means for nuclear reactors  

DOE Patents (OSTI)

An improved passive cooling arrangement is disclosed for maintaining adjacent or related components of a nuclear reactor within specified temperature differences. Specifically, heat pipes are operatively interposed between the components, with the vaporizing section of the heat pipe proximate the hot component operable to cool it and the primary condensing section of the heat pipe proximate the other and cooler component operable to heat it. Each heat pipe further has a secondary condensing section that is located outwardly beyond the reactor confinement and in a secondary heat sink, such as air ambient the containment, that is cooler than the other reactor component. Means such as shrouding normally isolated the secondary condensing section from effective heat transfer with the heat sink, but a sensor responds to overheat conditions of the reactor to open the shrouding, which thereby increases the cooling capacity of the heat pipe. By having many such heat pipes, an emergency passive cooling system is defined that is operative without electrical power.

Burelbach, James P. (Glen Ellyn, IL)

1984-01-01T23:59:59.000Z

163

Heat transfer pathways in underfloor air distribution (UFAD) systems  

E-Print Network (OSTI)

permission. QC-06-053 Heat Transfer Pathways in Underfloorchange the dynamics of heat transfer within a room as wellchange the dynamics of heat transfer within a room as well

Bauman, F.; Jin, H.; Webster, T.

2006-01-01T23:59:59.000Z

164

AN EXPERIMENTAL AND THEORETICAL STUDY OF HEAT TRANSFER WITH COMBUSTION  

E-Print Network (OSTI)

Figure 7.6. Thin film heat transfer gauge. I I il j i II· Figure 2. 2. Thin 1m heat transfer gauge. 'l' :i t jt IIIII. MEASUREMENTS AND HEAT TRANSFER IN THE SOLID Experiments

Heperkan, Hasan A.

2013-01-01T23:59:59.000Z

165

Clean Boiler Waterside Heat Transfer Surfaces  

SciTech Connect

This revised ITP tip sheet on cleaning boiler water-side heat transfer surfaces provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

2006-01-01T23:59:59.000Z

166

Nonequilibrium Electromagnetic Fluctuations: Heat Transfer and Interactions  

E-Print Network (OSTI)

The Casimir force between arbitrary objects in equilibrium is related to scattering from individual bodies. We extend this approach to heat transfer and Casimir forces in nonequilibrium cases where each body, and the ...

Kruger, Matthias

167

Daytime heat transfer processes over mountainous terrain  

Science Conference Proceedings (OSTI)

The daytime heat transfer mechanisms over mountainous terrain are investigated by means of large-eddy simulations over idealized valleys. Two- and three-dimensional topographies, corresponding to infinite and finite valleys, are used in order to ...

Juerg Schmidli

168

Rod Bundle Heat Transfer for Pressurized Water Reactors at Operating Conditions  

Science Conference Proceedings (OSTI)

Currently available heat transfer correlations for subcooled forced convection and subcooled boiling have not been validated with rod-array data at typical PWR fluid conditions. At the present time, rod bundle heat transfer processes cannot be analyzed with sufficient accuracy to make sound decisions regarding changes that might avoid an Axial Offset Anomaly (AOA).

2000-07-14T23:59:59.000Z

169

Heat Transfer and Reconnection Diffusion in Turbulent Magnetized Plasmas  

E-Print Network (OSTI)

It is well known that magnetic fields constrain motions of charged particles, impeding the diffusion of charged particles perpendicular to magnetic field direction. This modification of transport processes is of vital importance for a wide variety of astrophysical processes including cosmic ray transport, transfer of heavy elements in the interstellar medium, star formation etc. Dealing with these processes one should keep in mind that in realistic astrophysical conditions magnetized fluids are turbulent. In this review we single out a single transport process, namely, heat transfer and consider how it occurs in the presence of the magnetized turbulence. We show that the ability of magnetic field lines to constantly change topology and connectivity is at the heart of the correct description of the 3D magnetic field stochasticity in turbulent fluids. This ability is ensured by fast magnetic reconnection in turbulent fluids and puts forward the concept of reconnection diffusion at the core of the physical pictu...

Lazarian, A

2011-01-01T23:59:59.000Z

170

NEWTON: Greenhouse Gas and Heat Transfer  

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

Greenhouse Gas and Heat Transfer Greenhouse Gas and Heat Transfer Name: Robert Status: teacher Grade: 9-12 Location: AK Country: USA Date: Summer 2013 Question: It would appear from a superficial reading that heat flows out of a greenhouse gas more slowly than heat flows into the same gas. This has to be an incorrect interpretation. It seems more likely that molecules with high heat capacities resist heat transfer-both into and out of such a molecular system. At a molecular level how does heat move out of a hot greenhouse gas? I have seen plots of Cv vs Tempt which indicates that heat moves from translational modes of motion-into rotational modes and finally into modes of vibration. The energy spacing of vibrations is generally grater that rotation which are greater than translation. Could it be that it is this quantization of the energy levels and the difference in energy between such quantum states that is the source of the resistance to heat flow or transfer?

171

Program on Technology Innovation: Applications of Nanofluids to Enhance Heat Transfer in Nuclear Reactors  

Science Conference Proceedings (OSTI)

Advances in electronics and heat transfer systems require an improved energy removal rate from heated surfaces. Nanofluidsengineered colloidal dispersions of nano-size (1100 nm) particles in common fluids such as waterhave been found to enhance heat transfer properties. Because the primary mechanism of critical heat flux (CHF) enhancement results from the surface deposition of nanoparticles, nanofluids can be applied in two ways: through direct use as an advanced coolant and as a process coolant for in s...

2009-11-17T23:59:59.000Z

172

Heat exchanger with intermediate evaporating and condensing fluid  

DOE Patents (OSTI)

A shell and tube-type heat exchanger, such as a liquid sodium-operated steam generator for use in nuclear reactors, comprises a shell containing a primary fluid tube bundle, a secondary fluid tube bundle at higher elevation, and an intermediate fluid vaporizing at the surface of the primary fluid tubes and condensing at the surface of the secondary fluid tubes.

Fraas, Arthur P. (Knoxville, TN)

1978-01-01T23:59:59.000Z

173

Analysis of Heat Transfer in Metal Hydride Based Hydrogen Separation  

DOE Green Energy (OSTI)

This thesis presents a transient heat transfer analysis to model the heat transfer in the Pd/k packed column, and the impact of adding metallic foam.

Fleming, W.H. Jr.

1999-10-20T23:59:59.000Z

174

Aerodynamic Losses and Heat Transfer in a Blade Cascade with...  

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

Aerodynamic Losses and Heat Transfer in a Aerodynamic Losses and Heat Transfer in a Blade Cascade with 3 Blade Cascade with 3 - - D D Endwall Endwall Contouring Contouring...

175

Experimental study on turbulent natural convection heat transfer in ...  

Science Conference Proceedings (OSTI)

Feb 16, 2010 ... ments are conducted to investigate flow and heat transfer ... turbulent region, the heat transfer deterioration occurs for a bubble flow rate Q = 33 ...

176

Heat transfer via dropwise condensation on hydrophobic microstructured surfaces.  

E-Print Network (OSTI)

??Dropwise condensation has the potential to greatly increase heat transfer rates. Heat transfer coefficients by dropwise condensation and film condensation on microstructured silicon chips were… (more)

Ruleman, Karlen E. (Karlen Elizabeth)

2009-01-01T23:59:59.000Z

177

Characterization and Development of Advanced Heat Transfer Technologies (Presentation)  

DOE Green Energy (OSTI)

Advancing heat transfer technologies is a critical factor in power electronics equipment. NREL aims to characterize and develop advanced heat transfer technologies.

Abraham, T.

2007-11-08T23:59:59.000Z

178

Heat transfer in excimer laser melting of thin polysilicon layers  

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

Heat transfer in excimer laser melting of thin polysilicon layers Title Heat transfer in excimer laser melting of thin polysilicon layers Publication Type Journal Article Year of...

179

FILM COOLING CALCULATIONS WITH AN ITERATIVE CONJUGATE HEAT TRANSFER APPROACH USING EMPIRICAL HEAT TRANSFER COEFFICIENT CORRECTIONS.  

E-Print Network (OSTI)

??An iterative conjugate heat transfer technique was developed and automated to predict the temperatures on film cooled surfaces such as flat plates and turbine blades.… (more)

Dhiman, Sushant

2010-01-01T23:59:59.000Z

180

Nonequilibrium Electromagnetic Fluctuations: Heat Transfer and Interactions  

Science Conference Proceedings (OSTI)

The Casimir force between arbitrary objects in equilibrium is related to scattering from individual bodies. We extend this approach to heat transfer and Casimir forces in nonequilibrium cases where each body, and the environment, is at a different temperature. The formalism tracks the radiation from each body and its scatterings by the other objects. We discuss the radiation from a cylinder, emphasizing its polarized nature, and obtain the heat transfer between a sphere and a plate, demonstrating the validity of proximity transfer approximation at close separations and arbitrary temperatures.

Krueger, Matthias; Kardar, Mehran [Massachusetts Institute of Technology, Department of Physics, Cambridge, Massachusetts 02139 (United States); Emig, Thorsten [Laboratoire de Physique Theorique et Modeles Statistiques, CNRS UMR 8626, Ba circumflex timent 100, Universite Paris-Sud, 91405 Orsay cedex (France)

2011-05-27T23:59:59.000Z

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


181

Electrically heated liquid tank employing heat pipe heat transfer means  

SciTech Connect

The heating apparatus for applying heat to the interior of a chamber includes a modular, removable, electrical, heat-producing unit and a heat pipe mountable in a wall of the chamber with one end of the pipe arranged to receive heat from the electrical heat producing unit exterior of the housing and with another end of the pipe constructed and arranged to apply heat to the medium within the chamber. The heat pipe has high conductivity with a low temperature differential between the ends thereof and the heat producing unit includes an electric coil positioned about and removably secured to the one end of the heat pipe. The electric coil is embedded in a high thermal conducitivity, low electrical conductivity filler material which is surrounded by a low thermal conductivity insulating jacket and which is received around a metal core member which is removably secured to the one end of the heat pipe.

Shutt, J.R.

1978-12-26T23:59:59.000Z

182

Enhanced boiling heat transfer in horizontal test bundles  

Science Conference Proceedings (OSTI)

Two-phase flow boiling from bundles of horizontal tubes with smooth and enhanced surfaces has been investigated. Experiments were conducted in pure refrigerant R-113, pure R-11, and mixtures of R-11 and R-113 of approximately 25, 50, and 75% of R-113 by mass. Tests were conducted in two staggered tube bundles consisting of fifteen rows and five columns laid out in equilateral triangular arrays with pitch-to-diameter ratios of 1.17 and 1.5. The enhanced surfaces tested included a knurled surface (Wolverine`s Turbo-B) and a porous surface (Linde`s High Flux). Pool boiling tests were conducted for each surface so that reference values of the heat transfer coefficient could be obtained. Boiling heat transfer experiments in the tube bundles were conducted at pressures of 2 and 6 bar, heat flux values from 5 to 80 kW/m{sup 2}s, and qualities from 0% to 80%, Values of the heat transfer coefficients for the enhanced surfaces were significantly larger than for the smooth tubes and were comparable to the values obtained in pool boiling. It was found that the performance of the enhanced tubes could be predicted using the pool boiling results. The degradation in the smooth tube heat transfer coefficients obtained in fluid mixtures was found to depend on the difference between the molar concentration in the liquid and vapor.

Trewin, R.R.; Jensen, M.K.; Bergles, A.E.

1994-08-01T23:59:59.000Z

183

Apparatus and method for controlling heat transfer between a fluidized bed and tubes immersed therein  

DOE Patents (OSTI)

In a fluidized bed of solid particles having one or more heat exchange tubes immersed therein, the rate of heat transfer between the fluidized particles and a fluid flowing through the immersed heat exchange tubes is controlled by rotating an arcuate shield apparatus about each tube to selectively expose various portions of the tube to the fluidized particles.

Hodges, James L. (3 Hilltop Ave., Vernon, CT 06066); Cerkanowicz, Anthony E. (8 Fieldstone Dr., Livingston, NJ 07039)

1983-01-01T23:59:59.000Z

184

Apparatus and method for controlling heat transfer between a fluidized bed and tubes immersed therein  

DOE Patents (OSTI)

In a fluidized bed of solid particles having one or more heat exchange tubes immersed therein, the rate of heat transfer between the fluidized particles and a fluid flowing through the immersed heat exchange tubes is controlled by rotating an arcuate shield apparatus about each tube to selectively expose various portions of the tube to the fluidized particles.

Hodges, James L. (3 Hilltop Ave., Vernon, CT 06066); Cerkanowicz, Anthony E. (8 Fieldstone Dr., Livingston, NJ 07039)

1982-01-01T23:59:59.000Z

185

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

Science Conference Proceedings (OSTI)

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

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

2013-08-14T23:59:59.000Z

186

Heat transfer 1990. Proceedings of the ninth international heat transfer conference  

Science Conference Proceedings (OSTI)

This book contains the proceedings of the Ninth International Heat Transfer Conference. Included in Volume 6 are the following chapters: Local void fraction measurements in finned tube bundles, Unsteady heat and mass transfer in low two-phase flows and The effect of physical properties on drop size in annular flow.

Hetsroni, G.

1990-01-01T23:59:59.000Z

187

Radiative Heat Transfer between Neighboring Particles  

E-Print Network (OSTI)

The near-field interaction between two neighboring particles is known to produce enhanced radiative heat transfer. We advance in the understanding of this phenomenon by including the full electromagnetic particle response, heat exchange with the environment, and important radiative corrections both in the distance dependence of the fields and in the particle absorption coefficients. We find that crossed terms of electric and magnetic interactions dominate the transfer rate between gold and SiC particles, whereas radiative corrections reduce it by several orders of magnitude even at small separations. Radiation away from the dimer can be strongly suppressed or enhanced at low and high temperatures, respectively. These effects must be taken into account for an accurate description of radiative heat transfer in nanostructured environments.

Alejandro Manjavacas; F. Javier Garcia de Abajo

2012-01-26T23:59:59.000Z

188

Inverse Problems in Heat Transfer  

E-Print Network (OSTI)

This chapter presents a stochastic modeling and statistical inference approach to the solution of inverse problems in thermal transport systems. Of particular interest is the inverse heat conduction problem (IHCP) of estimating an unknown boundary heat flux in a conducting solid given temperature data within the domain. Even though deterministic sequential and whole time domain estimation methods have been applied with success over the years for the solution of such problems, we herein introduce stochastic approaches to representing and solving the IHCP. As most engineering systems and processes operate in an uncertain environment, it becomes increasingly important to address their analysis and inverse design in a stochastic manner using statistical data-driven prior and concurrent information on the system response. Recent advances in spectral stochastic modeling, computational Bayesian and spatial statistics enable complete and e#cient solution procedures to such problems. Two distinct approaches to the IHCP are presented in this chapter one based on spectral stochastic modeling and the other on Bayesian inference. Although these techniques are discussed in the context of the IHCP, the methodologies presented are general and applicable to design and estimation problems in other more complex problems in thermal transport systems including problems in the presence of convection, radiation and conduction. 1

Nicholas Zabaras

2004-01-01T23:59:59.000Z

189

Experimental Investigation of Bendable Heat Pipes.  

E-Print Network (OSTI)

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

ODHEKAR, DHANANJAY

2005-01-01T23:59:59.000Z

190

Power systems utilizing the heat of produced formation fluid  

DOE Patents (OSTI)

Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method includes treating a hydrocarbon containing formation. The method may include providing heat to the formation; producing heated fluid from the formation; and generating electricity from at least a portion of the heated fluid using a Kalina cycle.

Lambirth, Gene Richard (Houston, TX)

2011-01-11T23:59:59.000Z

191

Splice connector with internal heat transfer jacket  

DOE Patents (OSTI)

A heat transfer jacket is placed over the terminal portions of the conductors of a pair of high voltage cables which are connected in a splice connection wherein a housing surrounds the connected conductor portions, the heat transfer jacket extending longitudinally between the confronting ends of a pair of adaptor sleeves placed upon the insulation of the cables to engage and locate the adaptor sleeves relative to one another, and laterally between the conductors and the housing to provide a path of relatively high thermal conductivity between the connected conductor portions and the housing.

Silva, Frank A. (Basking Ridge, NJ); Mayer, Robert W. (Hackettstown, NJ)

1977-01-01T23:59:59.000Z

192

Nanoscale Heat Transfer: from Computation to Experiment  

E-Print Network (OSTI)

Heat transfer can differ distinctly at the nanoscale from that at the macroscale. Recent advancement in computational and experimental techniques has enabled a large number of interesting observations and understanding of heat transfer processes at the nanoscale. In this review, we will first discuss recent advances in computational and experimental methods used in nanoscale thermal transport studies, followed by reviews of novel thermal transport phenomena at the nanoscale observed in both computational and experimental studies, and discussion on current understanding of these novel phenomena. Our perspectives on challenges and opportunities on computational and experimental methods are also presented.

Luo, Tengfei

2013-01-01T23:59:59.000Z

193

Optimization of Phase Change Heat Transfer in Biporous Media  

E-Print Network (OSTI)

transfer analysis of a loop heat pipe with biporous wicks”.Planes”. Frontiers in Heat Pipes Journal 1, 013001 (2010).transfer model of a loop heat pipe with a bidisperse wick

Reilly, Sean

2013-01-01T23:59:59.000Z

194

Simulation of heat transfer in the unsaturated zone  

SciTech Connect

Heat transfer can play an important role in fluid flow near the emplacement site of high-level nuclear waste. The effects on far- field flow can be important in understanding net moisture fluxes above the repository zone. The convection in the unsaturated zone at the Yucca Mountain site was responsible for this movement. If this is so, then the convection could provide a mechanism for drying the rock above the repository zone and thus provide a buffer for heavy rainfall events. In addition, the convection would increase the movement of gaseous radionuclides such as {sup 14}CO{sub 2}, tritiated water vapor, and {sup 129}I (Weeks, 1987). Because of the complexity of the problem, numerical models were required to calculate gas flow and vapor transport at the site. Kipp previously modeled this problem using the code HST3D. This code represents the flow of a single-phase fluid with both heat- and mass-transfer effects included. Water density and partial pressure effects are accounted for by the virtual temperature method. In this paper, the problem was simulated using the code FEHMN, a finite-element heat- and mass-transfer code being developed for the Yucca Mountain Project. The work described in this paper was done in preparation of the upcoming problem to be formulated for the Performance Assessment Calculation Exercise. 5 refs., 9 figs., 1 tab.

Zyvoloski, G.

1990-02-01T23:59:59.000Z

195

Heat transfer research and power cycle transient modeling  

DOE Green Energy (OSTI)

Fine axial flutes enhance heat transfer in vertical shell-and-tube exchangers with water inside the tubes and ammonia evaporating or condensing in layer flow on the shell side. Single-tube experiments with R-11 and ammonia indicate local shell-side coefficients 3 to 5 times those for corresponding smooth tubes. Single-tube experiments with water indicate that at moderate velocities the tube-side coefficients are enhanced by a factor equal to the ratio of fluted-to-smooth surface areas while the fluid friction is similarly increased. The experimental data are transformed into mean individual coefficients for ammonia and water. Overall coefficients for a particular case are presented to illustrate the efficacy of enhancement by flutes on one or both sides of the heat transfer surface. Means are described for using emerging data to predict the static and dynamic behavior of the power cycle and the interactions of components throughout the complete power plant.

Rothfus, R.R.; Neuman, C.P.

1977-03-23T23:59:59.000Z

196

Heat and mass transfer in porous media  

DOE Green Energy (OSTI)

Field test data on the OOSI MR3 experiments are used as a basis for exhibiting the computational capabilities of the WAFE computer code, which is a generalized tool for the analysis of heat and mass transfer in multi-dimensional domains of porous geothermal materials.

Cook, T.L.; Harlow, F.H.; Travis, B.J.; Bartel, T.J.; Tyner, C.E.

1981-01-01T23:59:59.000Z

197

Cooperative heat transfer and ground coupled storage system  

DOE Patents (OSTI)

A cooperative heat transfer and ground coupled storage system wherein collected solar heat energy is ground stored and permitted to radiate into the adjacent ground for storage therein over an extended period of time when such heat energy is seasonally maximally available. Thereafter, when said heat energy is seasonally minimally available and has propagated through the adjacent ground a substantial distance, the stored heat energy may be retrieved by a circumferentially arranged heat transfer means having a high rate of heat transfer.

Metz, Philip D. (Rocky Point, NY)

1982-01-01T23:59:59.000Z

198

heat transfer | OpenEI Community  

Open Energy Info (EERE)

85 85 Varnish cache server Home Groups Community Central Green Button Applications Developer Utility Rate FRED: FRee Energy Database More Public Groups Private Groups Features Groups Blog posts Content Stream Documents Discussions Polls Q & A Events Notices My stuff Energy blogs 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load) Guru Meditation: XID: 2142229585 Varnish cache server heat transfer Home Dc's picture Submitted by Dc(15) Member 15 November, 2013 - 13:26 Living Walls ancient building system architect biomimicry building technology cooling cu daylight design problem energy use engineer fred andreas geothermal green building heat transfer heating living walls metabolic adjustment net zero pre-electricity Renewable Energy Solar university of colorado utility grid Wind

199

Coupled Reactor Kinetics and Heat Transfer Model for Heat Pipe Cooled Reactors  

SciTech Connect

Heat pipes are often proposed as cooling system components for small fission reactors. SAFE-300 and STAR-C are two reactor concepts that use heat pipes as an integral part of the cooling system. Heat pipes have been used in reactors to cool components within radiation tests (Deverall, 1973); however, no reactor has been built or tested that uses heat pipes solely as the primary cooling system. Heat pipe cooled reactors will likely require the development of a test reactor to determine the main differences in operational behavior from forced cooled reactors. The purpose of this paper is to describe the results of a systems code capable of modeling the coupling between the reactor kinetics and heat pipe controlled heat transport. Heat transport in heat pipe reactors is complex and highly system dependent. Nevertheless, in general terms it relies on heat flowing from the fuel pins through the heat pipe, to the heat exchanger, and then ultimately into the power conversion system and heat sink. A system model is described that is capable of modeling coupled reactor kinetics phenomena, heat transfer dynamics within the fuel pins, and the transient behavior of heat pipes (including the melting of the working fluid). The paper focuses primarily on the coupling effects caused by reactor feedback and compares the observations with forced cooled reactors. A number of reactor startup transients have been modeled, and issues such as power peaking, and power-to-flow mismatches, and loading transients were examined, including the possibility of heat flow from the heat exchanger back into the reactor. This system model is envisioned as a tool to be used for screening various heat pipe cooled reactor concepts, for designing and developing test facility requirements, for use in safety evaluations, and for developing test criteria for in-pile and out-of-pile test facilities.

WRIGHT,STEVEN A.; HOUTS,MICHAEL

2000-11-22T23:59:59.000Z

200

Heat transfer and pressure drop for air flow through enhanced passages. Final report  

SciTech Connect

An extensive experimental investigation was carried out to determine the pressure drop and heat transfer characteristics for laminar, transitional and turbulent flow of air through a smooth passage and twenty-three enhanced passages. The internal surfaces of all enhanced passages had spirally shaped geometries; these included fluted, finned/ribbed and indented surfaces. The Reynolds number (Re) was varied between 400 and 50000. The effect of heat transfer (wall cooling or fluid heating) on pressure drop is most significant within the transition region; the recorded pressure drop with heat transfer is much higher than that without heat transfer. The magnitude of this effect depends markedly on the average surface temperature and, to a lesser extent, on the geometric characteristics of the enhanced surfaces. When the pressure drop data are reduced as values of the Fanning friction factor(f), the results are about the same with and without heat transfer for turbulent flow, with moderate differences in the laminar and transition regions.

Obot, N.T.; Esen, E.B.

1992-06-01T23:59:59.000Z

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


201

Heat transfer and pressure drop for air flow through enhanced passages  

SciTech Connect

An extensive experimental investigation was carried out to determine the pressure drop and heat transfer characteristics for laminar, transitional and turbulent flow of air through a smooth passage and twenty-three enhanced passages. The internal surfaces of all enhanced passages had spirally shaped geometries; these included fluted, finned/ribbed and indented surfaces. The Reynolds number (Re) was varied between 400 and 50000. The effect of heat transfer (wall cooling or fluid heating) on pressure drop is most significant within the transition region; the recorded pressure drop with heat transfer is much higher than that without heat transfer. The magnitude of this effect depends markedly on the average surface temperature and, to a lesser extent, on the geometric characteristics of the enhanced surfaces. When the pressure drop data are reduced as values of the Fanning friction factor(f), the results are about the same with and without heat transfer for turbulent flow, with moderate differences in the laminar and transition regions.

Obot, N.T.; Esen, E.B.

1992-06-01T23:59:59.000Z

202

Numerical Investigation of Heat Transfer to Fully Developed Turbulent Air Flow in a Concentric Pipe  

Science Conference Proceedings (OSTI)

Numerical simulation using standard k-e turbulencemodel was developed to investigate numerically thecharacteristic of backward-facing step flow in a concentricpipe. This research is focused on the surface temperature, localheat transfer coefficient and ... Keywords: Numerical Simulation, Heat Transfer, Turbulent Flow, Computational Fluid Dynamics, Backward Facing Step

Cheen Sean Oon, Ahmad Badarudin, Salim Newaz Kazi, Arif Syazwan

2013-09-01T23:59:59.000Z

203

Heat Transfer between Graphene and Amorphous SiO2  

E-Print Network (OSTI)

We study the heat transfer between graphene and amorphous SiO2. We include both the heat transfer from the area of real contact, and between the surfaces in the non-contact region. We consider the radiative heat transfer associated with the evanescent electromagnetic waves which exist outside of all bodies, and the heat transfer by the gas in the non-contact region. We find that the dominant contribution to the heat transfer result from the area of real contact, and the calculated value of the heat transfer coefficient is in good agreement with the value deduced from experimental data.

B. N. J. Persson; H. Ueba

2010-07-22T23:59:59.000Z

204

Heat Transfer Analysis of Post-Weld Heat Treatment of Grade 91 Steel  

Science Conference Proceedings (OSTI)

The appropriate heat transfer coefficients are determined through the inverse heat conduction method utilizing ceramic heat blankets as well as a furnace as the ...

205

Reversible limit of processes of heat transfer  

E-Print Network (OSTI)

We study a process of heat transfer between a body of heat capacity C(T) and a sequence of N heat reservoirs, with temperatures equally spaced between an initial temperature T_0 and a final temperature T_N. The body and the heat reservoirs are isolated from the rest of the universe, and the body is brought in thermal contact successively with reservoirs of increasing temperature. We determine the change of entropy of the composite thermodynamic system in the total process in which the temperature of the body changes from T_0 to T_N. We find that for large values of N the total change of entropy of the composite process is proportional to (T_N-T_0)/N, but eventually a non-monotonic behavior is found at small values of N.

Stilck, Jürgen F

2013-01-01T23:59:59.000Z

206

Flexible profile approach to the conjugate heat transfer problem  

E-Print Network (OSTI)

The flexible profile approach proposed earlier to create CTM (compact or reduced order thermal models) is extended to cover the area of conjugate heat transfer. The flexible profile approach is a methodology that allows building a highly boundary conditions independent CTM, with any desired degree of accuracy, that may adequately replace detailed 3D models for the whole spectrum of applications in which the modeled object may be used. The extension to conjugate problems radically solves the problem of interfacing two different domains. Each domain, fluid or solid, can be "compacted" independently creating two CTM that can be joined together to produce reliable results for any arbitrary set of external boundary conditions.

M. -N. Sabry

2008-01-07T23:59:59.000Z

207

Modelling Heat Transfer in Nanofluids Based on Coupled MD ...  

Science Conference Proceedings (OSTI)

Simulations have shown that the additional heat transfer caused by the collision of the nanoparticles with the heat source contributes significantly to the ...

208

Optimization of Phase Change Heat Transfer in Biporous Media.  

E-Print Network (OSTI)

??As the heat transfer demands placed on small electronics devices increase, the demand for efficient evaporators for heat pipes and spreaders will increase in kind.… (more)

Reilly, Sean

2013-01-01T23:59:59.000Z

209

MODELING HEAT TRANSFER IN SPENT FUEL TRANSFER CASK NEUTRON SHIELDS – A CHALLENGING PROBLEM IN NATURAL CONVECTION  

SciTech Connect

In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 10-15 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper proposes that there may be reliable CFD approaches to the transfer cask problem, specifically coupled steady-state solvers or unsteady simulations; however, both of these solutions take significant computational effort. Segregated (uncoupled) steady state solvers that were tested did not accurately capture the flow field and heat transfer distribution in this application. Mesh resolution, turbulence modeling, and the tradeoff between steady state and transient solutions are addressed. Because of the critical nature of this application, the need for new experiments at representative scales is clearly demonstrated.

Fort, James A.; Cuta, Judith M.; Bajwa, C.; Baglietto, E.

2010-07-18T23:59:59.000Z

210

FEHM (Finite Element Heat and Mass Transfer Code)  

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

FEHM (Finite Element Heat and Mass Transfer Code) FEHM (Finite Element Heat and Mass Transfer Code) FEHM is used to simulate groundwater and contaminant flow and transport in deep...

211

Heat Transfer in Projecting and Sloped Fenestration Products  

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

Heat Transfer in Projecting and Sloped Fenestration Products Speaker(s): Dragan Charlie Curcija Date: May 26, 2010 - 12:00pm Location: 90-3122 The heat transfer performance of...

212

Heat transfer during film condensation of potassium vapor  

E-Print Network (OSTI)

The object of this work is to investigate theoretically and experimentally the following two phases of heat transfer during condensation of potassium vapore, a. Heat transfer during film condensation of pure saturated ...

Kroger, Detlev Gustav

1966-01-01T23:59:59.000Z

213

Situ soil sampling probe system with heated transfer line  

DOE Patents (OSTI)

The present invention is directed both to an improved in situ penetrometer probe and to a heated, flexible transfer line. The line and probe may be implemented together in a penetrometer system in which the transfer line is used to connect the probe to a collector/analyzer at the surface. The probe comprises a heater that controls a temperature of a geologic medium surrounding the probe. At least one carrier gas port and vapor collection port are located on an external side wall of the probe. The carrier gas port provides a carrier gas into the geologic medium, and the collection port captures vapors from the geologic medium for analysis. In the transfer line, a flexible collection line that conveys a collected fluid, i.e., vapor, sample to a collector/analyzer. A flexible carrier gas line conveys a carrier gas to facilitate the collection of the sample. A system heating the collection line is also provided. Preferably the collection line is electrically conductive so that an electrical power source can generate a current through it so that the internal resistance generates heat.

Robbat, Jr., Albert (Andover, MA)

2002-01-01T23:59:59.000Z

214

An experimental study of the flow and heat transfer between enhanced heat transfer plates for PHEs  

Science Conference Proceedings (OSTI)

The flow and heat transfer between inclined discrete rib plates for plate heat exchangers have been experimentally studied. Dye injection method is used to visualize the flow structures. The visualization results show that front vortex, rear vortex and main vortex are formed between the plates. The rib parameter influence is also studied using visualization method. The pressure drop and heat transfer between the inclined discrete rib plates as well as that between inclined continuous rib plates and smooth plates are also measured. The measured results show that the inclined discrete rib plate can enhanced heat transfer 20-25% at the same pumping power compared with the commonly used inclined continuous rib plates. (author)

Li, Xiao-wei [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Meng, Ji-an; Li, Zhi-xin [School of Aerospace, Tsinghua University, Beijing 100084 (China)

2010-11-15T23:59:59.000Z

215

Heat recirculating cooler for fluid stream pollutant removal  

DOE Patents (OSTI)

A process by which heat is removed from a reactant fluid to reach the operating temperature of a known pollutant removal method and said heat is recirculated to raise the temperature of the product fluid. The process can be utilized whenever an intermediate step reaction requires a lower reaction temperature than the prior and next steps. The benefits of a heat-recirculating cooler include the ability to use known pollutant removal methods and increased thermal efficiency of the system.

Richards, George A. (Morgantown, WV); Berry, David A. (Morgantown, WV)

2008-10-28T23:59:59.000Z

216

NISTIR 6299 A Heat Transfer Model for Fire Fighter's ...  

Science Conference Proceedings (OSTI)

Page 1. NISTIR 6299 A Heat Transfer Model for Fire Fighter's Protective Clothing William E. Mell J. Randall Lawson United ...

1999-05-06T23:59:59.000Z

217

Handbook of heat transfer fundamentals (2nd edition)  

SciTech Connect

Recent advances in heat transfer are discussed, providing data and methodology to solve a wide range of heat transfer problems. The topics considered include: basic concepts of heat transfer, mathematical methods, thermophysical properties, conduction, numerical methods in heat transfer, natural convection, and internal duct flow and external flows in forced convection. Also addressed are: rarefied gases, electric and magnetic fields, condensation, boiling, two-phase flow, and radiation.

Rohsenow, W.M.; Hartnett, J.P.; Ganic, E.N.

1985-01-01T23:59:59.000Z

218

Handbook of heat and mass transfer. Volumes 1 and 2  

Science Conference Proceedings (OSTI)

This two-volume series presents advanced topics in industrial heat and mass transfer operations for reactor design technology.

Cheremisinoff, N.P.

1985-01-01T23:59:59.000Z

219

Heat Transfer Characteristics of Magnetite under Microwave Irradiation  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2012 TMS Annual Meeting & Exhibition. Symposium , Materials Processing Fundamentals. Presentation Title, Heat Transfer ...

220

Heat Transfer Operators Associated with Quantum Operations  

E-Print Network (OSTI)

Any quantum operation applied on a physical system is performed as a unitary transformation on a larger extended system. If the extension used is a heat bath in thermal equilibrium, the concomitant change in the state of the bath necessarily implies a heat exchange with it. The dependence of the average heat transferred to the bath on the initial state of the system can then be found from the expectation value of a hermitian operator, which is named as the heat transfer operator (HTO). The purpose of this article is the investigation of the relation between the HTOs and the associated quantum operations. Since, any given quantum operation on a system can be realized by different baths and unitaries, many different HTOs are possible for each quantum operation. On the other hand, there are also strong restrictions on the HTOs which arise from the unitarity of the transformations. The most important of these is the Landauer erasure principle. This article is concerned with the question of finding a complete set of restrictions on the HTOs that are associated with a given quantum operation. An answer to this question has been found only for a subset of quantum operations. For erasure operations, these characterizations are equivalent to the generalized Landauer erasure principle. For the case of generic quantum operations however, it appears that the HTOs obey further restrictions which cannot be obtained from the entropic restrictions of the generalized Landauer erasure principle.

Ç. Aksak; S. Turgut

2010-02-03T23:59:59.000Z

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


221

Heat transfer of finned tube bundles in crossflow  

SciTech Connect

This volume correlates findings on heat transfer and hydraulic drag of bundles of finned tubes in crossflow at Reynolds numbers from 10/sup 4/ to 10/sup 6/. These studies illustrate fin, local, and mean heat transfer coefficients; effects of geometric parameters of the fins; effect of tube location within the bundle on heat transfer and hydraulic drag; and resistance of finned tube bundles.

Stasiulevicius, J.; Skrinska, A.; Zukauskas, A.

1988-01-01T23:59:59.000Z

222

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

DOE Green Energy (OSTI)

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

Piyush Sabharwall; Mike Patterson; Fred Gunnerson

2008-09-01T23:59:59.000Z

223

Molecular Dynamics Simulations of Heat Transfer In Nanoscale Liquid Films  

E-Print Network (OSTI)

Molecular Dynamics (MD) simulations of nano-scale flows typically utilize fixed lattice crystal interactions between the fluid and stationary wall molecules. This approach cannot properly model thermal interactions at the wall-fluid interface. In order to properly simulate the flow and heat transfer in nano-scale channels, an interactive thermal wall model is developed. Using this model, the Fourier’s law of heat conduction is verified in a 3.24 nm height channel, where linear temperature profiles with constant thermal conductivity is obtained. The thermal conductivity is verified using the predictions of Green-Kubo theory. MD simulations at different wall wettability ( ??f /? ) and crystal bonding stiffness values (K) have shown temperature jumps at the liquid/solid interface, corresponding to the well known Kapitza resistance. Using systematic studies, the thermal resistance length at the interface is characterized as a function of the surface wettability, thermal oscillation frequency, wall temperature and thermal gradient. An empirical model for the thermal resistance length, which could be used as the jump-coefficient of a Navier boundary condition, is developed. Temperature distributions in the nano-channels are predicted using analytical solution of the continuum heat conduction equation subjected to the new temperature jump condition, and validated using the MD results. Momentum and heat transfer in shear driven nanochannel flows are also investigated. Work done by the viscous stresses heats the fluid, which is dissipated through the channel walls, maintained at isothermal conditions. Spatial variations in the fluid density, kinematic viscosity, shear- and energy dissipation rates are presented. The energy dissipation rate is almost a constant for ??f /? < 0.6, which results in parabolic temperature profiles in the domain with temperature jumps due to the Kapitza resistance at the liquid/solid interfaces. Using the energy dissipation rates predicted by MD simulations and the continuum energy equation subjected to the temperature jump boundary conditions developed in this study, the analytical solutions are obtained for the temperature profiles, which agree well with the MD results.

Kim, Bo Hung

2009-05-01T23:59:59.000Z

224

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures  

E-Print Network (OSTI)

Comparison of various heat transfer coefficient models inpool boiling In summary, high heat transfer coefficientin boiling heat transfer can be generally explained by the

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

225

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

E-Print Network (OSTI)

Forced Convection Heat Transfer in Curved RectangularInfluence of Curvature on Heat Transfer to IncompressibleT. , "Forced Convective Heat Transfer in a Curved Channel

Yee, G.

2010-01-01T23:59:59.000Z

226

Heat Transfer Limitations in Hydrogen Production Via Steam Reformation: The Effect of Reactor Geometry  

E-Print Network (OSTI)

Ohsawa, Katsuyuki, “Heat Transfer Enhancement in Methanolsin the Catalyst Bed”, Heat Transfer-Asian Research, Vol.CA FUELCELL2006-97109 HEAT TRANSFER LIMITATIONS IN HYDROGEN

Vernon, David R.; Davieau, David D.; Dudgeon, Bryce A.; Erickson, Paul A.

2006-01-01T23:59:59.000Z

227

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures  

E-Print Network (OSTI)

and condensation processes in heat transfer equipment, 2ndand condensation processes in heat transfer equipment, in,the convection process, the heat transfer coefficient of

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

228

Some investigations on the enhancement of boiling heat transfer from planer surface embedded with continuous open tunnels  

Science Conference Proceedings (OSTI)

Boiling heat transfer from a flat surface can be enhanced if continuous open tunnel type structures are embedded in it. Further, improvement of boiling heat transfer from such surfaces has been tried by two separate avenues. At first, inclined tunnels are embedded over the solid surface and an effort is made to optimize the tunnel inclination for boiling heat transfer. Surfaces are manufactured in house with four different inclinations of the tunnels with or without a reentrant circular pocket at the end of the tunnel. Experiments conducted in the nucleate boiling regime showed that 45 deg inclination of the tunnels for both with and without base geometry provides the highest heat transfer coefficient. Next, active fluid rotation was imposed to enhance the heat transfer from tunnel type surfaces with and without the base geometry. Rotational speed imparted by mechanical stirrer was varied over a wide range. It was observed that fluid rotation enhances the heat transfer coefficient only up to a certain value of stirrer speed. Rotational speed values, beyond this limit, reduce the boiling heat transfer severely. A comparison shows that embedding continuous tunnel turns out to be a better option for the increase of heat transfer coefficient compared to the imposition of fluid rotation. But the behavior of inclined tunnels under the action of fluid rotation is yet to be established and can be treated as a future scope of the work. (author)

Das, A.K.; Das, P.K.; Saha, P. [Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur 721 302 (India)

2010-11-15T23:59:59.000Z

229

TURBULENT HEAT TRANSPORT IN TWO-AND THREE-DIMENSIONAL TEMPERATURE FIELDS  

E-Print Network (OSTI)

Most fluid flows and heat transfer processes of practicalfor turbulent heat and mass transfer processes. The study

Samaraweera, D.S.A.

2011-01-01T23:59:59.000Z

230

Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects  

E-Print Network (OSTI)

Q ? Al in the heat transfer process and the relation betweenv and Q ? Br in the heat transfer process, and the relationan internal cavity. This heat transfer process for the heat

Armijo, Kenneth Miguel

2011-01-01T23:59:59.000Z

231

Heat Transfer Correlation for Finned Casks  

SciTech Connect

Design of finned casks for dissipation of heat from radioactive decay usually requires reliance on generalized correlations in the literature which do not necessarily apply to the specific cask design. A correlation was developed, based on temperature profile measurements, for the design of upright cylindrical casks with vertical fins for convective and radiant heat transfer to ambient air. Temperature data at various heat loads were obtained for two different cask sizes of the same basic design. Each cask is mounted on a steel pallet and contained within a steel mesh cage. The smaller cask, which has 23 fins, has been approved (DOT-SP-6321) for shipment of up to 1400 W (th), and approval is being obtained (AEC AL USA/9503 BLF) for shipment of up to 3500 W heat load in the larger, 60-fin cask. The applicable theoretical equations were fit to the temperature data for both casks by simply adjusting the value used for the number of fins. The resulting correlation provides a reliable method for interpolation and extrapolation and for design of similar finned casks.

Griffin, J. F.

1974-04-01T23:59:59.000Z

232

Effects of winglets to augment tube wall heat transfer in louvered fin heat exchangers  

E-Print Network (OSTI)

Effects of winglets to augment tube wall heat transfer in louvered fin heat exchangers Paul A Abstract The louvered fin heat exchanger, a type of compact heat exchanger, has been used heavily transfer along the tube wall of the compact heat exchanger through the use of winglets placed

Thole, Karen A.

233

CORRELATING EVAPORATION HEAT TRANSFER COEFFICIENT OF REFRIGERANT R-134a IN A PLATE HEAT EXCHANGER  

E-Print Network (OSTI)

1 CORRELATING EVAPORATION HEAT TRANSFER COEFFICIENT OF REFRIGERANT R-134a IN A PLATE HEAT EXCHANGER for evaporation heat transfer coefficient of refrigerant R-134a flowing in a plate heat exchanger. Correlation heat exchanger are found to result in large discrepancies with their own experimental data

Kandlikar, Satish

234

Characteristics of multimode heat transfer in a differentially-heated horizontal rectangular duct.  

E-Print Network (OSTI)

??This study presents the numerical analysis of steady laminar flow heat transfer in a horizontal rectangular duct with differential heating on the vertical walls. Three… (more)

Wangdhamkoom, Panitan

2007-01-01T23:59:59.000Z

235

Factors affecting oscillating motion and heat transfer in an oscillating heat pipe .  

E-Print Network (OSTI)

??As demand has grown for thermal management solutions, interest in passive heat transfer devices such as heat pipes has grown as well. In particular, oscillating… (more)

Smoot, Christopher

2013-01-01T23:59:59.000Z

236

Heat transfer assembly for a fluorescent lamp and fixture  

DOE Patents (OSTI)

In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure. 11 figs.

Siminovitch, M.J.; Rubenstein, F.M.; Whitman, R.E.

1992-12-29T23:59:59.000Z

237

Heat transfer assembly for a fluorescent lamp and fixture  

DOE Patents (OSTI)

In a lighting fixture including a lamp and a housing, a heat transfer structure is disclosed for reducing the minimum lamp wall temperature of a fluorescent light bulb. The heat transfer structure, constructed of thermally conductive material, extends from inside the housing to outside the housing, transferring heat energy generated from a fluorescent light bulb to outside the housing where the heat energy is dissipated to the ambient air outside the housing. Also disclosed is a method for reducing minimum lamp wall temperatures. Further disclosed is an improved lighting fixture including a lamp, a housing and the aforementioned heat transfer structure.

Siminovitch, Michael J. (Richmond, CA); Rubenstein, Francis M. (Berkeley, CA); Whitman, Richard E. (Richmond, CA)

1992-01-01T23:59:59.000Z

238

Segmented heat exchanger  

DOE Patents (OSTI)

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

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

2010-12-14T23:59:59.000Z

239

Variational formulations for resting irreversible fluids with heat flow  

Science Conference Proceedings (OSTI)

Nonequilibrium statistical mechanics helps to estimate corrections to the entropy and energy of the fluid with heat flux in terms of the nonequilibrium distribution function, f. This leads to the coefficients of wave model of heat: relaxation ... Keywords: conservation laws, entropy, grad solution, variational calculus, wave equations

Stanislaw Sieniutycz; Piotr Kuran

2008-09-01T23:59:59.000Z

240

Flow and heat transfer in gas turbine disk cavities subject to nonuniform external pressure field  

SciTech Connect

Ingestion of hot gas from the main-stream gas path into turbine disk cavities, particularly the first-stage disk cavity, has become a serious concern for the next-generation industrial gas turbines features high rotor inlet temperature. Fluid temperature in the cavities increases further due to windage generated by fluid drag at the rotating and stationary surfaces. The resulting problem of rotor disk heat-up is exacerbated by the high disk rim temperature due to adverse (relatively flat) temperature profile of the mainstream gas in the annular flow passage of the turbine. This describes an investigation into local convective heat transfer coefficient and cooling effectiveness of the rotor disk, flow field in the disk cavity, computation of the flow field and heat transfer in the disk cavity, and mainstream gas injection and rotor disk cooling effectiveness by mass transfer analogy.

Roy, R.P.; Kim, Y.W.; Tong, T.W. [Arizona State Univ., Tempe, AZ (United States). Dept. of Mechanical and Aerospace Engineering

1995-12-31T23:59:59.000Z

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


241

HEAT TRANSFER AND TRITIUM PRODUCING SYSTEM  

DOE Patents (OSTI)

This invention related to a circulating lithium-containing blanket system in a neution source hav'ing a magnetic field associated therewith. The blanket serves simultaneously and efficiently as a heat transfer mediunm and as a source of tritium. The blanket is composed of a lithium-6-enriched fused salt selected from the group consisting of lithium nitrite, lithium nitrate, a mixture of said salts, a mixture of each of said salts with lithium oxide, and a mixture of said salts with each other and with lithium oxide. The moderator, which is contained within the blanket in a separate conduit, can be water. A stellarator is one of the neutron sources which can be used in this invention. (AEC)

Johnson, E.F.

1962-06-01T23:59:59.000Z

242

Modeling of data center airflow and heat transfer: State of the art and future trends  

Science Conference Proceedings (OSTI)

An assessment of the current thermal modeling methodologies for data centers is presented, with focus on the use of computational fluid dynamics and heat transfer as analysis tools, and model validation. Future trends in reduced or compact modeling of ... Keywords: Data center, Reduced order models, Thermal modeling

Jeffrey Rambo; Yogendra Joshi

2007-06-01T23:59:59.000Z

243

Heat transfer in bundles of finned tubes in crossflow  

SciTech Connect

This book provides correlations of heat transfer and hydraulic data for bundles of finned tubes in crossflow at high Reynolds numbers. Results of studies of the effectiveness of the fin, local, and mean heat transfer coefficients are presented. The effect of geometric parameters of the fins and of the location of tubes in the bundle on heat transfer and hydraulic drag are described. The resistance of the finned tube bundles under study and other factors are examined.

Stasiulevicius, J.; Skrinska, A.; Zukauskas, A.; Hewitt, G.F.

1986-01-01T23:59:59.000Z

244

ETTM - Heat Transfer Calculations Version 1.0  

Science Conference Proceedings (OSTI)

ETTM Heat Transfer Calculations is a computer based training module that allows users to access training when desired and review it at their own pace. It provides graphics and limited interactive features to enhance learning. This module reviews the basic engineering principles used to calculate heat transfer and how to apply these principles to typical nuclear plant applications. The calculation of heat transfer in plant systems is an important element of many engineering calculations. Students should r...

2010-09-27T23:59:59.000Z

245

A numerical model of convective heat transfer in a three dimensional channel with baffles  

E-Print Network (OSTI)

A numerical investigation of laminar forced convective heat transfer was performed in a three-dimensional channel with baffles in which a uniform heat flux was applied to the top and bottom walls, and the side walls were considered adiabatic. The trade-off between heat transfer enhancement and pressure drop produced by the baffles was studied for periodically fully developed flow (PDF). The numerical analysis was performed using a finite volume approach. The computer code was validated against the experimental results of Goldstein and Kreid (1967) and Beavers et. al. (1970) for a three-dimensional laminar flow in a channel without baffles. Parametric runs were made for Reynolds Numbers (Re) of 150, 250, 3 50, and 450, for blockage ratios (H/Dy) of 0. 5, 0.6, 0. 7, 0.8. Heat transfer behavior was studied for Prandtl Numbers (Pr) of 0. 7 and 7. 0, and for wall thermal conductivity to fluid thermal conductivity ratios (K) of 1, 10, 100 and 1000. It was found that three dimensional effects were present for the range of Reynolds number studied. The pressure drop penalty becomes highly important above blockage ratios of 0.7. Higher heat transfer enhancement was found for high Prandtl numbers (Pr--7. 0) than for low Prandtl numbers (Pr--O. 7). The heat transfer enhancement due to an increase in the thermal conductivity ratio of the solid to the fluid regions is greater than the one obtained by increasing the blockage ratio.

Lopez Buso, Jorge Ricardo

1995-01-01T23:59:59.000Z

246

Study on the Interfacial Heat Transfer Coefficient of High Pressure ...  

Science Conference Proceedings (OSTI)

The heat transfer behavior between an AM60B alloy casting and die during .... for Spent Nuclear Fuel and Measuring the Composition of Molten Salt by Using ...

247

A versatile procedure for calculating heat transfer through windows  

SciTech Connect

Advances in window technologies and the desire to standardize the reporting of standard window heat transfer indices have necessitated the development of a comprehensive analytical procedure for calculating heat transfer through windows. This paper shows how complete window heat transfer can be considered as the area-weighted sum of the three window component areas: the center-of-glass area, the edge-of-glass area, and the frame area. Algorithms for calculating heat transfer through each of these areas and for combining these to calculate total window indices are presented. 36 refs., 5 figs., 6 tabs.

Arasteh, D.K.; Reilly, M.S.; Rubin, M.D.

1989-05-01T23:59:59.000Z

248

Impact of Heat Transfer Media on Materials for Concentrated Solar ...  

Science Conference Proceedings (OSTI)

Presentation Title, Impact of Heat Transfer Media on Materials for Concentrated Solar Power. Author(s), Dane Wilson. On-Site Speaker (Planned), Dane Wilson.

249

Estimation of Heat Transfer Coefficient in Squeeze Casting of ...  

Science Conference Proceedings (OSTI)

The casting-die interfacial heat transfer coefficient(IHTC) in 5-step casting was .... from First-Principles: Solid-Solution Strengthening, Softening, and Cross-Slip.

250

Characterization and Development of Advanced Heat Transfer Technologies (Presentation)  

DOE Green Energy (OSTI)

This presentation gives an overview of the status and FY09 accomplishments for the NREL thermal management research project 'Characterization and Development of Advanced Heat Transfer Technologies'.

Kelly, K.

2009-05-01T23:59:59.000Z

251

Determination of Heat Transfer Coefficient Distribution at Part ...  

Science Conference Proceedings (OSTI)

... of oil flow on the heat transfer coefficient (HTC) distribution at the gear surface. ... Multiphase Flow in a Steelmaking Converter Using an Unconventional Lance.

252

Applications of COMSOL Multiphysics Software to Heat Transfer Processes.  

E-Print Network (OSTI)

??This thesis used the study of Heat Transfer and COMSOL Multiphysics software as a reference which was made for the purpose of future education in… (more)

Xiong, Wei

2010-01-01T23:59:59.000Z

253

NREL Improves Window Heat Transfer Calculations (Fact Sheet)...  

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

and interior radiation. The most significant errors were found in detailed window heat transfer algorithms due to implementation problems. The results show a decrease in...

254

Heat Transfer through Materials: Application to Silica Aerogels...  

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

Heat Transfer through Materials: Application to Silica Aerogels and Building Envelopes Speaker(s): Brangre Lartigue Date: December 19, 2005 - 12:00pm Location: Bldg. 90 After...

255

Phase Change Materials for Enhancing Heat Transfer in Thermal ...  

Science Conference Proceedings (OSTI)

One of the main issues with using phase change materials is that solidification often reduces total heat transfer, reducing the efficiency of the storage system.

256

Rotating Heat Transfer in High Aspect Ratio Rectangular Cooling...  

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

Reynolds Number (Nu Nu o ) (f f o ) 24% Increase in Cooling Performance Rotating Heat Transfer in High Aspect Ratio Rectangular Cooling Passages with Shaped Turbulators...

257

CFD Modelling of Heat Transfer in Supersonic Nozzles for ... - TMS  

Science Conference Proceedings (OSTI)

May 1, 2007 ... CFD Modelling of Heat Transfer in Supersonic Nozzles for Magnesium Production by Peter Witt, M.N.H. Khan, and Geoffrey Brooks ...

258

Enhanced boiling heat transfer by submerged, vibration induced jets .  

E-Print Network (OSTI)

??In this analysis, the efficacy of cavitation jets for heat transfer enhancement was demonstrated. The cavitation jet was formed from a cluster of cavitation bubbles… (more)

Tillery, Steven W.

2005-01-01T23:59:59.000Z

259

Evaluation of Transient Heat Transfer Coefficient Evolution in ...  

Science Conference Proceedings (OSTI)

As known, physical and geometrical aspects play a fundamental role on the heat transfer conditions during the solidification process. This high dependence of ...

260

HEAT TRANSFER IN UNDERGROUND HEATING EXPERIMENTS IN GRANITE, STRIPA, SWEDEN  

E-Print Network (OSTI)

CLOSED-FORM INTEGRAL SOLUTIONS FOR LINEAR HEAT CONDUCTION.For linear heat conduction in a homogeneous, isotropiclaw of similitude for linear heat conduction was utilized to

Chan, T.

2010-01-01T23:59:59.000Z

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


261

2.51 Intermediate Heat and Mass Transfer, Fall 2001  

E-Print Network (OSTI)

Analysis, modeling, and design of heat and mass transfer processes with application to common technologies. Unsteady heat conduction in one or more dimensions, steady conduction in multidimensional configurations, numerical ...

Lienhard, John H., 1961-

262

Heat transfer and pressure drop in tape generated swirl flow  

E-Print Network (OSTI)

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 ...

Lopina, Robert F.

1967-01-01T23:59:59.000Z

263

Heat pumps and under floor heating as a heating system for Finnish low-rise residential buildings.  

E-Print Network (OSTI)

??In bachelor’s thesis the study of under floor heating system with ground source heat pump for the heat transfers fluid heating is considered. The case… (more)

Chuduk, Svetlana

2010-01-01T23:59:59.000Z

264

Heat transfer and condensation of water vapour from humid air in compact heat exchangers.  

E-Print Network (OSTI)

??In this thesis, an experimental and simulation study of heat transfer in water-to-air compact-plate heat exchanger is presented. A compact-plate heat exchanger made of polypropylene,… (more)

Saraireh, Mohammad

2012-01-01T23:59:59.000Z

265

WSEAS-HMT'08-Kostic, PAGE 1 of 2 HMT'08-The 5th WSEAS International Conference on HEAT and MASS TRANSFER  

E-Print Network (OSTI)

. It has been applied to measure heat transfer coefficients of water flowing in a round tube k/cPr pµ= (-) exp experimental q& heat flow rate by unit of volume (W.m -3 ) f fluid R radius (m) i, performed in the GRESPI laboratory of Reims, was to estimate heat transfer coefficients between the flowing

Kostic, Milivoje M.

266

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

Science Conference Proceedings (OSTI)

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

Ali J. Chamkha

2008-03-01T23:59:59.000Z

267

Nanofluids for Heat Transfer: An Engineering Approach  

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

nanoparticle suspension; particle size; particle shape; base fluid; interfacial thermal resistance. Corresponding Author: Elena V Timofeeva Corresponding Author's...

268

Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump  

DOE Patents (OSTI)

Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use the working solution of the absorption system for the heat transfer medium. A combination of weak and rich liquor working solution is used as the heat transfer medium.

Phillips, Benjamin A. (Benton Harbor, MI); Zawacki, Thomas S. (St. Joseph, MI)

1996-12-03T23:59:59.000Z

269

SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer  

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

High Operating Temperature Liquid Metal Heat Transfer Fluids High Operating Temperature Liquid Metal Heat Transfer Fluids UCLA logo University of California Berkeley logo Yale logo Four graphics in a grid that represent the sputtering technique being used in this project. Combinatorial screening and high throughput characterization of materials will be used to identify, develop, and demonstrate metal alloys that meet the MURI HOT Fluids targets suitable for CSP applications. The University of California, Los Angeles, the University of California, Berkeley, and Yale University The University of California, Los Angeles (UCLA), along with partners at the University of California, Berkeley, and Yale University, under the 2012 Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids funding opportunity, is investigating the use of metal alloys as a heat transfer fluid (HTF) in concentrating solar power (CSP) systems operating at temperatures in excess of 800°C. By allowing higher temperature operation, CSP systems can achieve greater efficiencies and thereby reduce the overall cost of electricity production.

270

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

E-Print Network (OSTI)

Passive cooling via natural circulation of gas after a loss of coolant (LOCA) accident is one of the major goals of the Gas-cooled Fast Reactor (GFR). Due to its high surface heat flux and low coolant velocities under ...

Lee, Jeongik

2007-01-01T23:59:59.000Z

271

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

E-Print Network (OSTI)

Passive cooling via natural circulation of gas after a loss of coolant (LOCA) accident is one of the major goals of the Gas-cooled Fast Reactor (GFR). Due to its high surface heat flux and low coolant velocities under ...

Lee, Jeongik

272

Generator-absorber-heat exchange heat transfer apparatus and method and use thereof in a heat pump  

DOE Patents (OSTI)

Numerous embodiments and related methods for generator-absorber heat exchange (GAX) are disclosed, particularly for absorption heat pump systems. Such embodiments and related methods use the working solution of the absorption system for the heat transfer medium.

Phillips, Benjamin A. (Benton Harbor, MI); Zawacki, Thomas S. (St. Joseph, MI); Marsala, Joseph (Glen Ellyn, IL)

1994-11-29T23:59:59.000Z

273

Developing Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools  

E-Print Network (OSTI)

860. Batchelor, G.K. 1954. Heat transfer by free convectionfree convection. In: Heat Transfer and Turbulent BuoyantHEAT2, A PC-program for heat transfer in two dimensions.

Gustavsen, Arild

2009-01-01T23:59:59.000Z

274

DOE Funds 15 New Projects to Develop Solar Power Storage and Heat Transfer  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Funds 15 New Projects to Develop Solar Power Storage and Heat Funds 15 New Projects to Develop Solar Power Storage and Heat Transfer Projects For Up to $67.6 Million DOE Funds 15 New Projects to Develop Solar Power Storage and Heat Transfer Projects For Up to $67.6 Million September 19, 2008 - 3:43pm Addthis WASHINGTON - U.S. Department of Energy (DOE) today announced selections for negotiations of award under the Funding Opportunity Announcement (FOA), Advanced Heat Transfer Fluids and Novel Thermal Storage Concepts for Concentrating Solar Power Generation. These 15 new projects, for up to approximately $67.6 million, will facilitate the development of lower-cost energy storage for concentrating solar power (CSP) technology. These projects support President Bush's Solar America Initiative, which aims to make solar energy cost-competitive with conventional forms of electricity

275

Heat and moisture transfer through clothing  

E-Print Network (OSTI)

capacitance of clothing. Heat capacity of the clothing hasSuffix a cl c e m n r s area (m²) specific heat capacity (J/kgK) heat capacity (J/K) clothing surface area factor view

Voelker, Conrad; Hoffmann, Sabine; Kornadt, Oliver; Arens, Edward; Zhang, Hui; Huizenga, Charlie

2009-01-01T23:59:59.000Z

276

Enhanced radiative heat transfer between nanostructured gold plates  

E-Print Network (OSTI)

We compute the radiative heat transfer between nanostructured gold plates in the framework of the scattering theory. We predict an enhancement of the heat transfer as we increase the depth of the corrugations while keeping the distance of closest approach fixed. We interpret this effect in terms of the evolution of plasmonic and guided modes as a function of the grating's geometry.

R. Guérout; J. Lussange; F. S. S. Rosa; J. -P. Hugonin; D. A. R. Dalvit; J. -J. Greffet; A. Lambrecht; S. Reynaud

2012-03-07T23:59:59.000Z

277

The heat transfer mechanism in aqueous foam flow in a channel  

Science Conference Proceedings (OSTI)

The Heat transfer mechanism in two-phase aqueous foam flow was investigated for developing energy-efficient heat exchangers. Such heat exchangers can provide low consumption of energy resources due to enhanced heat transfer rates. An enhanced heat transfer ... Keywords: aqueous foam flow, heat exchangers, heat transfer

Irena Gabrielaitien?; Jonas Gylys; Rolandas Jonynas; Tadas Ždankus

2011-12-01T23:59:59.000Z

278

Dual circuit embossed sheet heat transfer panel  

DOE Patents (OSTI)

A heat transfer panel provides redundant cooling for fusion reactors or the like environment requiring low-mass construction. Redundant cooling is provided by two independent cooling circuits, each circuit consisting of a series of channels joined to inlet and outlet headers. The panel comprises a welded joinder of two full-size and two much smaller partial-size sheets. The first full-size sheet is embossed to form first portions of channels for the first and second circuits, as well as a header for the first circuit. The second full-sized sheet is then laid over and welded to the first full-size sheet. The first and second partial-size sheets are then overlaid on separate portions of the second full-sized sheet, and are welded thereto. The first and second partial-sized sheets are embossed to form inlet and outlet headers, which communicate with channels of the second circuit through apertures formed in the second full-sized sheet. 6 figs.

Morgan, G.D.

1984-02-21T23:59:59.000Z

279

Dual circuit embossed sheet heat transfer panel  

DOE Patents (OSTI)

A heat transfer panel provides redundant cooling for fusion reactors or the like environment requiring low-mass construction. Redundant cooling is provided by two independent cooling circuits, each circuit consisting of a series of channels joined to inlet and outlet headers. The panel comprises a welded joinder of two full-size and two much smaller partial-size sheets. The first full-size sheet is embossed to form first portions of channels for the first and second circuits, as well as a header for the first circuit. The second full-sized sheet is then laid over and welded to the first full-size sheet. The first and second partial-size sheets are then overlaid on separate portions of the second full-sized sheet, and are welded thereto. The first and second partial-sized sheets are embossed to form inlet and outlet headers, which communicate with channels of the second circuit through apertures formed in the second full-sized sheet.

Morgan, Grover D. (St. Louis County, MO)

1984-01-01T23:59:59.000Z

280

Heat transfer between elastic solids with randomly rough surfaces  

E-Print Network (OSTI)

We study the heat transfer between elastic solids with randomly rough surfaces. We include both the heat transfer from the area of real contact, and the heat transfer between the surfaces in the noncontact regions. We apply a recently developed contact mechanics theory, which accounts for the hierarchical nature of the contact between solids with roughness on many different length scales. For elastic contact, at the highest (atomic) resolution the area of real contact typically consists of atomic (nanometer) sized regions, and we discuss the implications of this for the heat transfer. For solids with very smooth surfaces, as is typical in many modern engineering applications, the interfacial separation in the non-contact regions will be very small, and for this case we show the importance of the radiative heat transfer associated with the evanescent electromagnetic waves which exist outside of all bodies.

B. N. J. Persson; B. Lorenz; A. I. Volokitin

2009-08-27T23:59:59.000Z

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


281

Heat transfer in oscillating flows with sudden change in cross section  

DOE Green Energy (OSTI)

Oscillating fluid flow (zero mean) with heat transfer, between two parallel plates with a sudden change in cross section, was examined computationally. The flow was assumed to be laminar and incompressible with inflow velocity uniform over the channel cross section but varying sinusoidally with time. Over 30 different cases were examined; these cases cover wide ranges of Re{sub max} (187.5 to 30,000), Va (1 to 350), expansion ratio (1:2, 1:4, 1:8, and 1:12) and A{sub r} (0.68 to 4). Three different geometric cases were considered (asymmetric expansion/contraction, symmetric expansion/contraction, and symmetric blunt body). The heat transfer cases were based on constant wall temperature at higher (heating) or lower (cooling) value than inflow fluid temperature. As a result of the oscillating flow, the fluid undergoes sudden expansion in one-half of the cycle and sudden contraction in the other half. In this paper, one heating case is examined in detail, and conclusions are drawn from all the cases (documented in detail elsewhere). Instantaneous friction factors and heat transfer coefficients, for some ranges, of Re{sub max} and Va, deviated substantially from those predicted with steady-state correlations.

Ibrahim, M.; Hashim, W. [Cleveland State Univ., OH (United States); Tew, R.C.; Dudenhoefer, J.E. [Lewis Research Center, Cleveland, OH (United States)

1994-09-01T23:59:59.000Z

282

Heat transfer in inertial confinement fusion reactor systems  

SciTech Connect

The transfer of energy produced by the interaction of the intense pulses of short-ranged fusion microexplosion products with materials is one of the most difficult problems in inertially-confined fusion (ICF) reactor design. The short time and deposition distance for the energy results in local peak power densities on the order of 10/sup 18/ watts/m/sup 3/. High local power densities may cause change of state or spall in the reactor materials. This will limit the structure lifetimes for ICF reactors of economic physical sizes, increasing operating costs including structure replacement and radioactive waste management. Four basic first wall protection methods have evolved: a dry-wall, a wet-wall, a magnetically shielded wall, and a fluid wall. These approaches are distinguished by the way the reactor wall interfaces with fusion debris as well as the way the ambient cavity conditions modify the fusion energy forms and spectra at the first wall. Each of these approaches requires different heat transfer considerations.

Hovingh, J.

1979-05-14T23:59:59.000Z

283

Liquid Crystal Technique Application for Heat Transfer Investigation in a Fin-Tube Heat Exchanger Element  

Science Conference Proceedings (OSTI)

The use of thermochromic liquid crystal technique (LCT) and true-colour image processing system in heat transfer modelling is described. Experimental procedure, led on rig at Technical University of Gdansk, cover full-field flow patterns in heat exchanger ... Keywords: heat transfer, thermochromic liquid crystals, vortex generator, wind tunnel

M. Wierzbowski; J. Stasiek

2002-04-01T23:59:59.000Z

284

Method and apparatus for improving heat transfer in a fluidized bed  

DOE Patents (OSTI)

An apparatus contains a fluidized bed that includes particles of different triboelectrical types, each particle type acquiring an opposite polarity upon contact. The contact may occur between particles of the two types or between particles of etiher type and structure or fluid present in the apparatus. A fluidizing gas flow is passed through the particles to produce the fluidized bed. Immersed within the bed are electrodes. An alternating EMF source connected to the electrodes applies an alternating electric field across the fluidized bed to cause particles of the first type to move relative to particles of the second type and relative to the gas flow. In a heat exchanger incorporating the apparatus, the electrodes are conduits conveying a fluid to be heated. The two particle types alternately contact each conduit to transfer heat from a hot gas flow to the second fluid within the conduit.

Lessor, Delbert L. (Richland, WA); Robertus, Robert J. (Richland, WA)

1990-01-01T23:59:59.000Z

285

Error Analysis of Heat Transfer for Finned-Tube Heat-Exchanger Text-Board  

E-Print Network (OSTI)

In order to reduce the measurement error of heat transfer in water and air side for finned-tube heat-exchanger as little as possible, and design a heat-exchanger test-board measurement system economically, based on the principle of test-board system error analyses and design, the equation of measurement error of heat transfer in air side and water side about orifice meter for the finned-tube heat-exchanger was obtained. This paper studies the major factors that may influence the largest admitted measurement error of measurement instruments for heat transfer in water and air side, and analyzes the degree that water temperature and pressure measurement influence heat transfer in water side, and the degree that wet bulb temperature difference measurement influences heat transfer in air side. Finally, this paper indicates that the key problem of reducing heat transfer in water side is water temperature measurement of the in-out pipe of heat-exchanger, and wet bulb temperature difference is a key to decrease the heat transfer in air side for finned-tube heat-exchanger. This paper gives a theoretical instruction for designing the measurement system of a finned-tube heat-exchanger test-board

Chen, Y.; Zhang, J.

2006-01-01T23:59:59.000Z

286

Enhanced two phase flow in heat transfer systems  

DOE Patents (OSTI)

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.

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

2013-12-03T23:59:59.000Z

287

Development of a carburizing and quenching simulation tool: Determination of heat transfer boundary conditions in salt  

Science Conference Proceedings (OSTI)

In the numerical simulation of the quenching of steel parts, it is desirable to limit the thermal problem to one of conduction in the solid part, with Newtonian cooling on the surface. This avoids the solution of highly transient, non-Boussinesq conjugate heat transfer problems which often involve mixed convection. Of course, the heat transfer coefficient h{sub 1} is in general a function of local surface temperature, and may depend strongly on the part geometry and other parameters. In order to obtain appropriate heat transfer coefficients for quenching thick rings in salt, we solve the conjugate heat transfer problem for representative geometries and determine the heat transfer coefficient from the calculated heat flux at the solid-fluid interface. This is done in a two-stage approach. First, we examine fully coupled solutions obtained from first principles without adjustable empirical parameters using an adaptive finite difference code applicable to simple shapes. The purpose of this part of the procedure is to gain insight into the physics of immersion, free convection and forced convection and to determine the most appropriate forms of the physical properties in the salt. Validation for simple shapes is accomplished by comparison with experimental data reported in the literature. Second, empirical modifications to physical properties and simplified governing equations are used to account for conduction-dominated heat transfer on initial contact and subsequent forced convection during immersion, based on results of the first calculations, so that a commercial finite-volume CFD code can be used to model complex shapes and flow in a quench tank. These results are compared with experimental data for thick rings quenched in salt, and used to calculate surface heat transfer coefficients as functions of temperature and location from the resulting heat flux at the part surface.

Shick, D. [Torrington Co., CT (United States); Walton, H. [Torrington Co., Rutherfordton, NC (United States); Chenoweth, D.R. [Sandia National Lab., Livermore, CA (United States)] [and others

1996-10-01T23:59:59.000Z

288

Handbook of heat and mass transfer. Volume 2  

Science Conference Proceedings (OSTI)

This two-volume series, the work of more than 100 contributors, presents advanced topics in industrial heat and mass transfer operations and reactor design technology. Volume 2 emphasizes mass transfer and reactor design. Some of the contents discussed are: MASS TRANSFER PRINCIPLES - Effect of turbulence promoters on mass transfer. Mass transfer principles with homogeneous and heterogeneous reactions. Convective diffusion with reactions in a tube. Transient mass transfer onto small particles and drops. Modeling heat and mass transport in falling liquid films. Heat and mass transfer in film absorption. Multicomponent mass transfer: theory and applications. Diffusion limitation for reaction in porous catalysts. Kinetics and mechanisms of catalytic deactivation. DISTILLATION AND EXTRACTION - Generalized equations of state for process design. Mixture boiling. Estimating vapor pressure from normal boiling points of hydrocarbons. Estimating liquid and vapor molar fractions in distillation columns. Principles of multicomponent distillation. Generalized design methods for multicomponent distillation. Interfacial films in inorganic substances extraction. Liquid-liquid extraction in suspended slugs. MULTIPHASE REACTOR SYSTEMS - Reaction and mass transport in two-phase reactors. Mass transfer and kinetics in three-phase reactors. Estimating liquid film mass transfer coefficients in randomly packed columns. Designing packed tower wet scrubbers - emphasis on nitrogen oxides. Gas absorption in aerated mixers. Axial dispersion and heat transfer in gas-liquid bubble columns. Operation and design of trickle-bed reactors.

Cheremisinoff, N.P.

1986-01-01T23:59:59.000Z

289

Cryogenic apparatus for study of near-field heat transfer  

Science Conference Proceedings (OSTI)

For bodies spaced in vacuum at distances shorter than the wavelength of the thermal radiation, radiative heat transfer substantially increases due to the contribution of evanescent electromagnetic waves. Experimental data on heat transfer in near-field regime are scarce. We have designed a cryogenic apparatus for the study of heat transfer over microscopic distances between metallic and non-metallic surfaces. Using a mechanical positioning system, a planeparallel gap between the samples, concentric disks, each 35 mm in diameter, is set and varied from 10{sup 0} to 10{sup 3} {mu}m. The heat transferred from the hot (10 - 100 K) to the cold sample ({approx}5 K) sinks into a liquid helium bath through a thermal resistor, serving as a heat flux meter. Transferred heat power within {approx}2 nW/cm{sup 2} and {approx}30 {mu}W/cm{sup 2} is derived from the temperature drop along the thermal resistor. For tungsten samples, the distance of the near-field effect onset was inversely proportional to temperature and the heat power increase was observed up to three orders of magnitude greater than the power of far-field radiative heat transfer.

Kralik, T.; Hanzelka, P.; Musilova, V.; Srnka, A.; Zobac, M. [Institute of Scientific Instruments of the ASCR, v.v.i., Kralovopolska 147, Brno (Czech Republic)

2011-05-15T23:59:59.000Z

290

Intermediate Heat Transfer Loop Study for High Temperature Gas-Cooled Reactor  

DOE Green Energy (OSTI)

A number of possible configurations for a system that transfers heat between the nuclear reactor and the hydrogen and/or electrical generation plants were identified. These configurations included both direct and indirect cycles for the production of electricity. Both helium and liquid salts were considered as the working fluid in the intermediate heat transport loop. Methods were developed to perform thermal-hydraulic and cycleefficiency evaluations of the different configurations and coolants. The thermal-hydraulic evaluations estimated the sizes of various components in the intermediate heat transport loop for the different configurations. This paper also includes a portion of stress analyses performed on pipe configurations.

C. H. Oh; C. Davis; S. Sherman

2008-08-01T23:59:59.000Z

291

Trace formulas for nonequilibrium Casimir interactions, heat radiation, and heat transfer for arbitrary objects  

E-Print Network (OSTI)

We present a detailed derivation of heat radiation, heat transfer, and (Casimir) interactions for N arbitrary objects in the framework of fluctuational electrodynamics in thermal nonequilibrium. The results can be expressed ...

Bimonte, Giuseppe

292

Measurement of flow field and local heat transfer distribution on a scraped heat exchanger crystalliser surface  

E-Print Network (OSTI)

Measurement of flow field and local heat transfer distribution on a scraped heat exchanger.ravelet@laposte.net Geert-Jan Witkamp G.J.Witkamp@xs4all.nl Abstract In a cylindrical scraped heat exchanger crystallizer exchanger surface has been studied by direct measurements of the heat exchanger surface temperature

Paris-Sud XI, Université de

293

Downflow heat transfer in a heated ribbed vertical annulus with a cosine power profile  

Science Conference Proceedings (OSTI)

Experiments designed to investigate downflow heat transfer in a heated, ribbed annulus test section simulating one of the annular coolant channels of a Savannah River Plant production reactor Mark 22 fuel assembly have been conducted at the Idaho National Engineering Laboratory. The inner surface of the annulus was constructed of aluminum and was electrically heated to provide an axial cosine power profile and a flat azimuthal power shape. Data presented in this report are from the ECS-2c series, which was a follow on series to the ECS-2b series, conducted specifically to provide additional data on the effect of different powers at the same test conditions, for use in evaluation of possible power effects on the aluminum temperature measurements. Electrical powers at 90%, 100%, and 110% of the power required to result in the maximum aluminum temperature at fluid saturation temperature were used at each set of test conditions previously used in the ECS-2b series. The ECS-2b series was conducted in the same test rig as the previous ECS-2b series. Data and experimental description for the ECS-2b series is provided in a previous report. 18 refs., 25 figs., 3 tabs.

Anderson, J.L.; Condie, K.G.; Larson, T.K.

1991-10-01T23:59:59.000Z

294

Modeling of Heat Transfer in Rooms in the Modelica Buildings Library  

E-Print Network (OSTI)

for convective and radiative heat transfer yielded a twofoldModeling of Heat Transfer in Rooms in the Modelica “of California. MODELING OF HEAT TRANSFER IN ROOMS IN THE

Wetter, Michael

2013-01-01T23:59:59.000Z

295

Rheology and Convective Heat Transfer of Colloidal Gas Aphrons in Horizontal Minichannels  

E-Print Network (OSTI)

Single-phase convective heat transfer in microchannels: aand Newell, M. E. , 1967. Heat transfer in fully developed3 /s at 130 W. Water CGA Heat Transfer Coefficient, h (W/m 2

Tseng, H.; Pilon, L.; Warrier, G.

2006-01-01T23:59:59.000Z

296

Heat-transfer dynamics during cryogen spray cooling of substrate at different initial temperatures  

E-Print Network (OSTI)

Aguilar G 2004 Radial heat transfer dynamics during cryogenof droplet dynamics and heat transfer in spray cooling Exp.S0031-9155(04)84030-2 Heat-transfer dynamics during cryogen

Jia, W; Aguilar, G; Wang, G X; Nelson, J S

2004-01-01T23:59:59.000Z

297

MEASUREMENTS OF HEAT TRANSFER TO HELIUM II AT ATMOSPHERIC PRESSURE IN A CONFINED GEOMETRY  

E-Print Network (OSTI)

M. X. Francois-:- "Heat Transfer Properties in a VerticalK. T - Tb (K) Fig. 4 . Heat transfer at the lambda point.B. The difference in the heat transfer characteristics on

Warren, R.P.

2011-01-01T23:59:59.000Z

298

Analytical and numerical solution of one- and two-dimensional steady heat transfer in a coldplate  

SciTech Connect

We develop analytical models for steady-state, one- and two-dimensional heat transfer in a single-material, flat-plate coldplate. Discrete heat sources are mounted on one side of the plate and heat transfer to a flowing fluid occurs on the other. The models are validated numerically using finite differences. We propose a simple procedure for estimating maximum coldplate temperature at the location of each heat source which includes thermal interaction among the sources. Results from one model are compared with data obtained for a composite coldplate operated in the laboratory. We demonstrate the utility of the models as diagnostic tools to be used for predicting the existence and extent of void volumes and delaminations in the composite material that can occur with coldplates of this type. Based on our findings, recommendations for effective coldplate design are given.

Jones, G.F.; Bennett, G.A.; Bultman, D.H.

1987-01-01T23:59:59.000Z

299

Khounsary Named Associate Editor of ASME Journal of Heat Transfer  

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

New Science with the APS Superconducting Undulator New Science with the APS Superconducting Undulator Young of XSD Named Associate Editor of New Journal "Structural Dynamics" The Daguerreotype and the X-ray: A Deep Look Questions Rise about Seeding For Ocean C02 Sequestration X-ray Method Shows How Frog Embryos Could Help Thwart Disease APS News Archives: 2012 | 2011 | 2010 | 2009 2008 | 2007 | 2006 | 2005 2004 | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed Khounsary Named Associate Editor of ASME Journal of Heat Transfer October 22, 2013 Bookmark and Share Ali Khounsary Ali Khounsary of the APS Engineering Support Division has been appointed as an Associate Editor of the ASME Journal of Heat Transfer. The Journal of Heat Transfer, in publication since 1879, "disseminates information of permanent interest in the areas of heat and mass transfer.

300

FEHM (Finite Element Heat and Mass Transfer Code)  

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

FEHM (Finite Element Heat and Mass Transfer Code) FEHM (Finite Element Heat and Mass Transfer Code) FEHM (Finite Element Heat and Mass Transfer Code) FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. June 29, 2013 software FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. Available for thumbnail of Feynman Center (505) 665-9090 Email FEHM (Finite Element Heat and Mass Transfer Code) FEHM is used to simulate groundwater and contaminant flow and transport in deep and shallow, fractured and un-fractured porous media throughout the US DOE complex. FEHM has proved to be a valuable asset on a variety of

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


301

Survey and evaluation of techniques to augment convective heat transfer  

E-Print Network (OSTI)

This report presents a survey and evaluation of the numerous techniques which have been shown to augment convective heat transfer. These techniques are: surface promoters, including roughness and treatment; displaced ...

Bergles A. E.

1965-01-01T23:59:59.000Z

302

Wind heat transfer coefficient in solar collectors in outdoor conditions  

Science Conference Proceedings (OSTI)

Knowledge of wind heat transfer coefficient, h{sub w}, is required for estimation of upward losses from the outer surface of flat plate solar collectors/solar cookers. In present study, an attempt has been made to estimate the wind induced convective heat transfer coefficient by employing unglazed test plate (of size about 0.9 m square) in outdoor conditions. Experiments, for measurement of h{sub w}, have been conducted on rooftop of a building in the Institute campus in summer season for 2 years. The estimated wind heat transfer coefficient has been correlated against wind speed by linear regression and power regression. Experimental values of wind heat transfer coefficient estimated in present work have been compared with studies of other researchers after normalizing for plate length. (author)

Kumar, Suresh; Mullick, S.C. [Centre for Energy Studies, Indian Institute of Technology, Delhi, Hauz Khas, New Delhi 110 016 (India)

2010-06-15T23:59:59.000Z

303

Aspects of Heat Transfer During Production of Remelt Ingot Using ...  

Science Conference Proceedings (OSTI)

Sep 1, 2001 ... Aspects of Heat Transfer During Production of Remelt Ingot Using Chain Casters by J.E Grandfield, TT Nguyen, G. Redden and J.A. Taylor ...

304

Design and fabrication of heat transfer surfaces from superplastic material  

Science Conference Proceedings (OSTI)

The production of complex heat transfer surfaces (i.e., those without straight fins) is restricted by available fabrication techniques, materials, geometries, and cost. Based on the superplastic sheet thermoforming process, a new technique for fabricating ...

J. B. Randolph; F. K. King

1972-05-01T23:59:59.000Z

305

Heat transfer during film condensation of a liquid metal vapor  

E-Print Network (OSTI)

The object of this investigation is to resolve the discrepancy between theory and experiment for the case of heat transfer durirnfilm condensation of liquid metal vapors. Experiments by previous investigators have yielded ...

Sukhatme, S. P.

1964-01-01T23:59:59.000Z

306

Investigation of 3-D Heat Transfer Effects in Fenestration Products.  

E-Print Network (OSTI)

??ABSTRACT INVESTIGATION OF 3-D HEAT TRANSFER EFFECTS IN FENESTRATION PRODUCTS SEPTEMBER 2010 SNEH KUMAR B. TECH., INDIAN INSTITUTE OF TECHNOLOGY, CHENNAI INDIA M.S.M.E., UNIVERSITY OF… (more)

Kumar, Sneh

2010-01-01T23:59:59.000Z

307

Industrial Heat Pumps Using Solid/Vapor Working Fluids  

E-Print Network (OSTI)

Industrial heat pumps have the potential to reduce the operating costs of chemical and heat treating processes in the chemical, petroleum, paper, dairy, and many other industries. The cost development of fossil fuel and other prime energy require excellent efficiency/cost ratios and hardware designs adaptable to specific process needs, in order to compete with vapor re-compression recovery systems. The state-of-the-art heat pump equipment employing liquid/vapor working fluids fulfills the requirements only in some applications. The employment of solid/vapor complex compounds leads to more cost effective heat recovery, which is due to simple hardware with no moving parts, extraordinary low maintenance effort, excellent temperature lifts avoiding the need of two-stage systems, and low first cost. This paper describes the advantages and disadvantages of solid/vapor working media.

Rockenfeller, U.

1986-06-01T23:59:59.000Z

308

On Water Flow in Hot Fractured Rock -- A Sensitivity Study on the Impact of Fracture-Matrix Heat Transfer  

E-Print Network (OSTI)

is related to the heat transfer between the two phasespossibly be affected. Heat transfer from the matrix can beof Fracture-Matrix Heat Transfer Jens T. Birkholzer and

Birkholzer, Jens T.; Zhang, Yingqi

2005-01-01T23:59:59.000Z

309

Thermal single-well injection-withdrawal tracer tests for determining fracture-matrix heat transfer area  

E-Print Network (OSTI)

Testing for Estimating Heat Transfer Area in FracturedFRACTURE-MATRIX HEAT TRANSFER AREA Karsten Pruess andimprove the flow and heat transfer characteristics of the

Pruess, K.

2011-01-01T23:59:59.000Z

310

A unified numerical framework model for simulating flow, transport, and heat transfer in porous and fractured media  

E-Print Network (OSTI)

Flow, Transport, and Heat Transfer in Porous and Fracturedtransport, and heat transfer in porous and fracturedflow, chemical transport, and heat transfer in rock. These

Wu, Yu-Shu

2004-01-01T23:59:59.000Z

311

A unified numerical framework model for simulating flow, transport, and heat transfer in porous and fractured media  

E-Print Network (OSTI)

transport, and heat transfer processes in porous media. 2.1.mass transport, and heat-transfer processes through porousinvolved. These heat-transfer processes are complicated by

Wu, Yu-Shu

2004-01-01T23:59:59.000Z

312

Enhancement of heat transfer for ground source heat pump systems.  

E-Print Network (OSTI)

??Uptake of geothermal heat pump (GSHP) systems has been slow in some parts of the world due to the unpredictable operational performance, large installation space… (more)

Mori, Hiromi

2010-01-01T23:59:59.000Z

313

Advanced turbine cooling, heat transfer, and aerodynamic studies  

DOE Green Energy (OSTI)

The contractual work is in three parts: Part I - Effect of rotation on enhanced cooling passage heat transfer, Part II - Effect of Thermal Barrier Coating (TBC) spallation on surface heat transfer, and Part III - Effect of surface roughness and trailing edge ejection on turbine efficiency under unsteady flow conditions. Each section of this paper has been divided into three parts to individually accommodate each part. Part III is further divided into Parts IIIa and IIIb.

Han, Je-Chin; Schobeiri, M.T. [Texas A & M Univ., College Station, TX (United States). Dept. of Mechanical Engineering

1995-12-31T23:59:59.000Z

314

Handbook of single-phase convective heat transfer  

Science Conference Proceedings (OSTI)

This book presents a comprehensive collection of convective heat transfer basics, methods of calculations, tables, charts and design parameters involving single-phase flows - the most commonly experienced mode in heat transfer problems. Topics covered include natural and forced convection under a wise variety of design conditions, such as ducts, crossflows, turbulent conditions, transitional states, curved and coiled ducts, over rods in metals and through bends, valves and fittings. The book provides sections on radiation interaction and fouling conditions.

Kakac, S.; Shah, R.K.; Aung, W.

1987-01-01T23:59:59.000Z

315

Mpemba effect, Newton cooling law and heat transfer equation  

E-Print Network (OSTI)

In this work we suggest a simple theoretical solution of the Mpemba effect in full agreement with known experimental data. This solution follows simply as an especial approximation (linearization) of the usual heat (transfer) equation, precisely linearization of the second derivation of the space part of the temperature function (as it is well-known Newton cooling law can be considered as the effective approximation of the heat (transfer) equation for constant space part of the temperature function).

Vladan Pankovic; Darko V. Kapor

2010-05-06T23:59:59.000Z

316

Effect of Channel Configurations for Tritium Transfer in Printed Circuit Heat Exchangers  

DOE Green Energy (OSTI)

The Next Generation Nuclear Plant (NGNP), a very High temperature Gas-Cooled Reactor (VHTR) concept, will provide the first demonstration of a closed-loop Brayton cycle at a commercial scale of a few hundred megawatts electric and hydrogen production. The power conversion system (PCS) for the NGNP will take advantage of the significantly higher reactor outlet temperatures of the VHTR to provide higher efficiencies than can be achieved in the current generation of light water reactors. Besides demonstrating a system design that can be used directly for subsequent commercial deployment, the NGNP will demonstrate key technology elements that can be used in subsequent advanced power conversion systems for other Generation IV reactors. In anticipation of the design, development and procurement of an advanced power conversion system for the NGNP, the system integration of the NGNP and hydrogen plant was initiated to identify the important design and technology options that must be considered in evaluating the performance of the proposed NGNP. In the VHTR system, an intermediate heat exchanger (IHX), which transfers heat from the reactor core to the electricity or hydrogen production system is one key component, and its effectiveness is directly related to the system overall efficiency. In the VHTRs, the gas fluids used for coolant generally have poor heat transfer capability, so it requires very large surface area for a given condition. For this reason, a compact heat exchanger (CHE), which is widely used in industry especially for gasto-gas or gas-to-liquid heat exchange is considered as a potential candidate for an IHX replacing the classical shell and tube type heat exchanger. A compact heat exchanger is arbitrary referred to be a heat exchanger having a surface area density greater than 700 m2/m3. The compactness is usually achieved by fins and micro-channels, and leads to the enormous heat transfer enhancement and size reduction. The surface area density is the total heat transfer area divided by the volume of the heat exchanger. In the case of PCHE units, the heat transfer surface area density may be as high as 2,500 m2/m3. This high compactness implies an appreciable reduction in material reducing cost. In this study, heat transfer and tritium penetration analyses have been performed for two different channel configurations of the PCHE; (1) standard and (2) off-set. One of the goals of this study was to determine whether offsetting the hot and cold streams would significantly reduce the tritium flux, and whether or not it would affect the heat transfer significantly.

Chang Oh; Eung Kim; Robert Shrake; Mike Patterson

2009-05-01T23:59:59.000Z

317

Literature survey of heat transfer enhancement techniques in refrigeration applications  

Science Conference Proceedings (OSTI)

A survey has been performed of the technical and patent literature on enhanced heat transfer of refrigerants in pool boiling, forced convection evaporation, and condensation. Extensive bibliographies of the technical literature and patents are given. Many passive and active techniques were examined for pure refrigerants, refrigerant-oil mixtures, and refrigerant mixtures. The citations were categorized according to enhancement technique, heat transfer mode, and tube or shell side focus. The effects of the enhancement techniques relative to smooth and/or pure refrigerants were illustrated through the discussion of selected papers. Patented enhancement techniques also are discussed. Enhanced heat transfer has demonstrated significant improvements in performance in many refrigerant applications. However, refrigerant mixtures and refrigerant-oil mixtures have not been studied extensively; no research has been performed with enhanced refrigerant mixtures with oil. Most studies have been of the parametric type; there has been inadequate examination of the fundamental processes governing enhanced refrigerant heat transfer, but some modeling is being done and correlations developed. It is clear that an enhancement technique must be optimized for the refrigerant and operating condition. Fundamental processes governing the heat transfer must be examined if models for enhancement techniques are to be developed; these models could provide the method to optimize a surface. Refrigerant mixtures, with and without oil present, must be studied with enhancement devices; there is too little known to be able to estimate the effects of mixtures (particularly NARMs) with enhanced heat transfer. Other conclusions and recommendations are offered.

Jensen, M.K.; Shome, B. [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Mechanical Engineering, Aeronautical Engineering and Mechanics

1994-05-01T23:59:59.000Z

318

Developing Low-Conductance Window Frames: Capabilities and Limitations of Current Window Heat Transfer Design Tools  

E-Print Network (OSTI)

internal cavities the heat transfer process is more complex,heat transfer in these “insulated” zones could be used in the design process

Gustavsen, Arild

2009-01-01T23:59:59.000Z

319

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink  

E-Print Network (OSTI)

-flow boiling over circular tube bundles has been meticulously studied; collected data and correlations for circular tube bundles. For exam- ple, Jensen and Hsu [81] conducted a parametric study of boiling heat transfer in a horizontal tube bundle and reported an increase in local heat transfer coefficient

Peles, Yoav

320

Research on Convective Heat Transfer and Mass Transfer of the Evaporator in Micro/Mini-Channel  

E-Print Network (OSTI)

With the development of science and technology, various heating and cooling equipment have a development trend of micromation. Micro-fabrication processes make it possible to conduct research on condensation heat transfer in micro-channels. Based on the reviewers on the present household air conditioners, the potential requirements for new heat transfer enhancement used for household air conditioners are discussed. Investigations on condensation and boiling of refrigerants in mini/micro channels have indicated that the evaporator and condenser of air conditioner would be more efficient and more compact by using microchannels, and hence it could improve the coefficient of performance of air conditioners to meet the new energy conversion standards in China. The relationship between condensation heat transfer of refrigerants and surface physical characteristics of the evaporator are pointed out and analyzed in order to achieving the corresponding heat transfer coefficients.

Su, J.; Li, J.

2006-01-01T23:59:59.000Z

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


321

Pool boiling heat transfer characteristics of nanofluids  

E-Print Network (OSTI)

Nanofluids are engineered colloidal suspensions of nanoparticles in water, and exhibit a very significant enhancement (up to 200%) of the boiling Critical Heat Flux (CHF) at modest nanoparticle concentrations (50.1% by ...

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

2007-01-01T23:59:59.000Z

322

Molecular Dynamics Method in Microscale Heat Transfer Shigeo Maruyama  

E-Print Network (OSTI)

1 Molecular Dynamics Method in Microscale Heat Transfer Shigeo Maruyama Department of Mechanical://www.photon.t.u-tokyo.ac.jp/~maruyama/ 1. INTRODUCTION Molecular level understandings are becoming more important and molecular based to take account of nuclei in size of molecular clusters. The effect of the surfactant on the heat and mass

Maruyama, Shigeo

323

Heat Transfer Laboratory of the Savannah River Laboratory  

SciTech Connect

The Heat Transfer Laboratory, recently- constructed adjacent to the main Savannah River Laboratory building, was designed to mock up nuclear heating and cooling of reactor components under a variety- of conditions. Nuclear heating is simulated by electrical resistance heating of test sections with a 3 MW directcurrent power supply. Cooling is provided by water. Three test stations (A, B, and C) are available for testing full-size fuel assemblies, measuring flow instabilities, and for measuring burnout heat fluxes. Safeguards provided in the design of the facility and conservative operating procedures minimize or elimnate potential hazards. (auth)

Knoebel, D.H.; Harris, S.D.

1973-10-01T23:59:59.000Z

324

Analysis of heat transfer processes and geothermal pattern in the Alberta Basin, Canada  

SciTech Connect

The transfer of heat from the crystalline basement of sedimentary basins to the atmosphere can be influenced to different degrees by the movement of formation waters within the complex structure of aquifers and aquitards in the basin. Past studies of the geothermal regime in the Western Canada Sedimentary Basin have shown the existence of a low geothermal gradient (low heat flux area) in the foothills region of southwestern Alberta, and of a high geothermal gradient (high heat flux area) in the lowlands in northeastern Alberta, close to the Precambrian Shield. These distributions of geothermal gradients and heat fluxes were attributed to the effects of basin wide groundwater flow. Hydrogeological studies in selected parts of the basin, and dimensional analysis applied to heat transfer processes show that the permeability of the sediments, and indeed the fluid velocities, are too low to play a significant role in the transport of terrestrial heat in the Alberta part of the Western Canada Sedimentary Basin. On a regional scale, the actual distributions of the heat flux and geothermal gradients are probably due to crustal thickening and/or increased radiogenic heat generation in the basement. Thermal anomalies, which may be due to granitic intrusions, are superimposed over this trend. At an intermediate scale, the geothermal field is controlled by topography, stratigraphy, and lithology of the sediments. Only on a local scale is the convection of heat important. copyright American Geophysical Union 1988

Bachu, S.

1988-07-10T23:59:59.000Z

325

Handbook of radiative heat transfer in high-temperature gases  

Science Conference Proceedings (OSTI)

This work offers both an original method for calculating optical properties of low-temperature plasma at elevated densities ... and an effective new means for calculating radiative heat transfer in hot gases and plasma with arbitrary temperature and pressure distributions. These methods allow for automatic accounting of all details of the plasma spectrum, including the line structure. This volume contains radiant transfer in problems of heat transfer; integration over frequency; methods of partial characteristics; method of effective populations; calculation of partial characteristics; appendix: tabular data.

Soloukhin, R.I.; Golovnev, I.F.; Zamurayev, V.P.; Katsnelson, S.S.; Kovalskaya, G.A.; Sevastyanenko, V.G.; Soloukhin, R.I.

1987-01-01T23:59:59.000Z

326

Non-equilibrium electromagnetic fluctuations: Heat transfer and interactions  

E-Print Network (OSTI)

The Casimir force between arbitrary objects in equilibrium is related to scattering from individual bodies. We extend this approach to heat transfer and Casimir forces in non-equilibrium cases where each body, and the environment, is at a different temperature. The formalism tracks the radiation from each body and its scatterings by the other objects. We discuss the radiation from a cylinder, emphasizing its polarized nature, and obtain the heat transfer between a sphere and a plate, demonstrating the validity of proximity transfer approximation at close separations and arbitrary temperatures.

Matthias Krüger; Thorsten Emig; Mehran Kardar

2011-02-18T23:59:59.000Z

327

Modulation of near-field heat transfer between two gratings  

E-Print Network (OSTI)

We present a theoretical study of near-field heat transfer between two uniaxial anisotropic planar structures. We investigate how the distance and relative orientation (with respect to their optical axes) between the objects affect the heat flux. In particular, we show that by changing the angle between the optical axes it is possible in certain cases to modulate the net heat flux up to 90% at room temperature, and discuss possible applications of such a strong effect.

Svend-Age Biehs; Felipe S. S. Rosa; Philippe Ben-Abdallah

2011-05-18T23:59:59.000Z

328

Active heat transfer enhancement in integrated fan heat sinks  

E-Print Network (OSTI)

Modern computer processors require significant cooling to achieve their full performance. The "efficiency" of heat sinks is also becoming more important: cooling of electronics consumes 1% of worldwide electricity use by ...

Staats, Wayne Lawrence

2012-01-01T23:59:59.000Z

329

Radiant heat transfer from storage casks to the environment  

SciTech Connect

A spent fuel storage cask must efficiently transfer the heat released by the fuel assemblies through the cask walls to the environment. This heat must be transferred through passive means, limiting the energy transfer mechanisms from the cask to natural convection and radiation heat transfer.. Natural convection is essentially independent of the characteristics of the array of casks, provided there is space between casks to permit a convection loop. Radiation heat transfer, however, depends on the geometric arrangement of the array of casks because the peripheral casks will shadow the interior casks and restrict radiant heat transfer from all casks to the environment. The shadowing of one cask by its neighbors is determined by a view factor that represents the fraction of radiant energy that leaves the surface of a cask and reaches the environment. This paper addresses the evaluation of the view factor between a centrally located spent fuel storage cask and the environment. By combining analytic expressions for the view factor of (1) infinitely long cylinders and (2) finite cylinders with a length-to-diameter ratio of 2 to represent spent fuel storage casks, the view factor can be evaluated for any practical array of spent fuel storage casks.

Carlson, R W; Hovingh, J; Thomas, G R

1999-05-10T23:59:59.000Z

330

Design and operation of solar thermal heat transfer systems  

Science Conference Proceedings (OSTI)

The importance of heat transfer systems in the collection and use of solar energy is discussed. The success or failure of many solar energy systems has been determined by the design of the heat transfer system. This report includes a short summary of some of the DOE sponsored solar industrial process heat sites. From the design, construction, and operation of these systems many lessons were learned which will be important to designers and potential users of solar thermal systems. Also included is a discussion of solar collector foundation over-design that has increased the collector system costs.

Rush, E.E.

1985-01-01T23:59:59.000Z

331

Tree-Shaped Fluid Flow and Heat Storage in a Conducting Solid  

Science Conference Proceedings (OSTI)

This paper documents the time-dependent thermal interaction between a fluid stream configured as a plane tree of varying complexity embedded in a conducting solid with finite volume and insulated boundaries. The time scales of the convection-conduction phenomenon are identified. Two-dimensional and three-dimensional configurations are simulated numerically. The number of length scales of the tree architecture varies from one to four. The results show that the heat transfer density increases, and the time of approach to equilibrium decreases as the complexity of the tree designs increases. These results are then formulated in the classical notation of energy storage by sensible heating, which shows that the effective number of heat transfer units increases as the complexity of the tree design increases. The complexity of heat transfer designs in many applications is constrained by first cost and operating cost considerations. This work provides a fundamental basis for objective evaluation of cost and performance tradeoffs in thermal design of energy systems with complexity as an unconstrained parameter that can be actively varied over a broad range to determine the optimum system design.

Combelles, L.; Lorente, S.; Anderson, R.; Bejan, A.

2012-01-01T23:59:59.000Z

332

Heat Transfer Enhancement in Separated and Vortex Flows  

SciTech Connect

This document summarizes the research performance done at the Heat Transfer Laboratory of the University of Minnesota on heat transfer and energy separation in separated and vortex flow supported by DOE in the period September 1, 1998--August 31, 2003. Unsteady and complicated flow structures in separated or vortex flows are the main reason for a poor understanding of heat transfer under such conditions. The research from the University of Minnesota focused on the following important aspects of understanding such flows: (1) Heat/mass transfer from a circular cylinder; (2) study of energy separation and heat transfer in free jet flows and shear layers; and (3) study of energy separation on the surface and in the wake of a cylinder in crossflow. The current study used three different experimental setups to accomplish these goals. A wind tunnel and a liquid tunnel using water and mixtures of ethylene glycol and water, is used for the study of prandtl number effect with uniform heat flux from the circular cylinder. A high velocity air jet is used to study energy separation in free jets. A high speed wind tunnel, same as used for the first part, is utilized for energy separation effects on the surface and in the wake of the circular cylinder. The final outcome of this study is a substantial advancement in this research area.

Richard J. Goldstein

2004-05-27T23:59:59.000Z

333

TRANSIENT HEAT TRANSFER IN REACTOR COOLANT CHANNELS  

SciTech Connect

An analysis is presented of the transient behavior of a generalized cooiant channel neglecting temperature dependent reactivity changes. The analysis is applicable to forced convection cooling of heterogeneous reactor fuel elements or electrically heated simulation thereof. Derivations are given for cases of variation of coolant inlet temperature and of heat generation. An approximation is also developed applicable to thin fuel elements. From this, solutions are obtained for cases-of impulsive, step, linear, and step-exponential variations of inlet temperature, and, of impulsive and uniform variations of heat generation. The solutions presented will be of use during preliminary stages of design of new heterogeneous reactor concepts (when the use of computing machines may not be warranted), and, in the design and interpretation of transient experiments simulating reactor fuel channels. (auth)

Stein, R.P.

1957-10-31T23:59:59.000Z

334

Experimental Investigation of Forced Convection Heat Transfer of Nanofluids in a Microchannel using Temperature Nanosensors  

E-Print Network (OSTI)

Experiments were performed to study forced convective heat transfer of de-ionized water (DI water) and aqueous nanofluids flowing in a microchannel. An array of temperature nanosensors, called “Thin Film Thermocouples (TFT)”, was utilized for performing the experimental measurements. TFT arrays were designed (which included design of photomask layout), microfabricated, packaged and assembled for testing with the experimental apparatus. Heat removal rates from the heated surface to the different testing fluids were measured by varying the coolant flow rates, wall temperatures, nanoparticle material, nanoparticle morphology (shape and nanoparticle size) as well as mass concentrations of nanoparticles in the coolants. Anomalous thermal behavior was observed in the forced convective heat transfer experiments. Precipitation of the nanoparticles on the heat exchanging surface was monitored using Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray spectroscopy (EDX). Isolated precipitation of nanoparticles is expected to cause formation of “nanofins” leading to enhancement of surface area and thus resulting in enhanced convective heat transfer to the nanofluid coolants. However, excessive precipitation (caused due to the agglomeration of the nanoparticles in the nanofluid coolant) causes scaling (fouling) of the heat exchanging surfaces and thus results in degradation of convective heat transfer. This study shows that the surface morphology plays a crucial role in determining the efficacy of convective heat transfer involving suspensions of nanoparticles in coolants (or nanofluids). Flow visualization and quantitative estimation of near-wall temperature profiles were performed using quantum dots and fluorescent dyes. This non-contact measurement technique for temperature and flow profiles in microchannels using quantum dots is expected to make pioneering contribution to the field of experimental flow visualization and to the study of micro/nano-scale heat transfer phenomena, particularly for forced convective heat transfer of various coolants, including nanofluids. Logical extensions of this study were explored and future directions were proposed. Preliminary experiments to demonstrate feasibility showed significant enhancement in the flow boiling heat flux values for nanofluids compared to that of pure solvent (DIW). Based on the novel phenomena observed in this study several other topics for future research were suggested, such as, using Surface Plasmon Resonance (SPR) platforms to monitor precipitation of nanoparticles on microchannel surfaces in real time (e.g., for generating surface isotherms).

Yu, Jiwon 1982-

2012-12-01T23:59:59.000Z

335

Heat Transfer Enhancement for Finned-Tube Heat Exchangers with Vortex Generators: Experimental and Numerical Results  

Science Conference Proceedings (OSTI)

A combined experimental and numerical investigation is under way to investigate heat transfer enhancement techniques that may be applicable to large-scale air-cooled condensers such as those used in geothermal power applications. The research is focused on whether air-side heat transfer can be improved through the use of finsurface vortex generators (winglets,) while maintaining low heat exchanger pressure drop. A transient heat transfer visualization and measurement technique has been employed in order to obtain detailed distributions of local heat transfer coefficients on model fin surfaces. Pressure drop measurements have also been acquired in a separate multiple-tube row apparatus. In addition, numerical modeling techniques have been developed to allow prediction of local and average heat transfer for these low-Reynolds-number flows with and without winglets. Representative experimental and numerical results presented in this paper reveal quantitative details of local fin-surface heat transfer in the vicinity of a circular tube with a single delta winglet pair downstream of the cylinder. The winglets were triangular (delta) with a 1:2 height/length aspect ratio and a height equal to 90% of the channel height. Overall mean fin-surface Nusselt-number results indicate a significant level of heat transfer enhancement (average enhancement ratio 35%) associated with the deployment of the winglets with oval tubes. Pressure drop measurements have also been obtained for a variety of tube and winglet configurations using a single-channel flow apparatus that includes four tube rows in a staggered array. Comparisons of heat transfer and pressure drop results for the elliptical tube versus a circular tube with and without winglets are provided. Heat transfer and pressure-drop results have been obtained for flow Reynolds numbers based on channel height and mean flow velocity ranging from 700 to 6500.

O'Brien, James Edward; Sohal, Manohar Singh; Huff, George Albert

2002-08-01T23:59:59.000Z

336

Heat Transfer in Superfluids: Effect of Gravity  

E-Print Network (OSTI)

We discuss the influence of an external field on energy transport in superfluid. He-II is not isothermal in presence of Earth gravity; instead, it supports finite temperature gradient given by a Fourier-like equation. We calculate asymptotic behavior of the effective heat resistance in the vicinity of the $\\lambda$-transition.

L. A. Melnikovsky

2004-05-19T23:59:59.000Z

337

Aspects of forced convective heat transfer in geothermal systems  

DOE Green Energy (OSTI)

A knowledge of convective heat transfer is essential to understanding geothermal systems and other systems of moving groundwater. A simple, kinematic approach toward convective heat transfer is taken here. Concern is not with the cause of the groundwater motion but only with the fact that the water is moving and transferring heat. The mathematical basis of convective heat transfer is the energy equation which is a statement of the first law of thermodynamics. The general solution of this equation for a specific model of groundwater flow has to be done numerically. The numerical algorithm used here employs a finite difference approximation to the energy equation that uses central differences for the heat conduction terms and one-sided differences for the heat convection terms. Gauss--Seidel iteration is then used to solve the finite difference equation at each node of a non-uniform mesh. The Monroe and Red Hill hot springs, a small hydrothermal system in central Utah, provide an example to illustrate the application of convective heat transfer theory to a geophysical problem. Two important conclusions regarding small geothermal systems follow immediately from the results of this application. First, the most rapid temperature rise in the convecting part of a geothermal system is near the surface. Below this initially rapid temperature increase the temperature increases very slowly, and thus temperatures extrapolated from shallow boreholes can be seriously in error. Second, the temperatures and heat flows observed at Monroe and Red Hill, and probably at many other small geothermal areas, can easily result from moderate vertical groundwater velocities in faults and fracture zones in an area of normal heat flow.

Kilty, K.; Chapman, D.S.; Mase, C.

1978-07-01T23:59:59.000Z

338

Heat transfer and pressure drop measurements in an air/molten salt direct-contact heat exchanger  

SciTech Connect

This paper presents a comparison of experimental data with a recently published model of heat exchange in irrigated packed beds. Heat transfer and pressure drop were measured in a 150 mm (ID) column with a 610-mm bed of metal Pall rings. Molten nitrate salt and preheated air were the working fluids with a salt inlet temperature of approximately 440{degree}C and air inlet temperatures of approximately 230{degree}C. A comparison between the experimental data and the heat transfer model is made on the basis of heat transfer from the salt. For the range of air and salt flow rates tested, 0.3 to 1.2 kg/m{sup 2} s air flow and 6 to 18 kg/m{sup 2} s salt flow, the data agree with the model within 22% standard deviation. In addition, a model for the column pressure drop was validated, agreeing with the experimental data within 18% standard deviation over the range of column pressure drop from 40 to 1250 Pa/m. 25 refs., 7 figs., 2 tabs.

Bohn, M.S.

1988-11-01T23:59:59.000Z

339

Thermodynamics of enhanced heat transfer: a model study  

E-Print Network (OSTI)

Situations where a spontaneous process of energy or matter transfer is enhanced by an external device are widespread in nature (human sweating system, enzyme catalysis, facilitated diffusion across bio-membranes, industrial heat exchangers). The thermodynamics of such processes remains however open. Here we study enhanced heat transfer by a model junction immersed between two thermal baths at different temperatures $T_h$ and $T_c$ ($T_h>T_c$). The transferred heat power is enhanced via controlling the junction by means of external time-dependent fields. Provided that the spontaneous heat flow process is optimized over the junction Hamiltonian, any enhancement of this spontaneous process does demand consumption and subsequent dissipation of work. The efficiency of enhancement is defined via the increment in the heat power divided over the amount of consumed work. We show that this efficiency is bounded from above by $T_c/(T_h-T_c)$. Formally this is identical to the Carnot bound for the efficiency of ordinary refrigerators which transfer heat from cold to hot. It also shares some (but not all) physical features of the Carnot bound.

Karen Hovhannisyan; Armen E. Allahverdyan

2010-07-20T23:59:59.000Z

340

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

SciTech Connect

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

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

1996-06-06T23:59:59.000Z

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


341

Preliminary Heat Transfer Studies for the Double Shell Tanks (DST) Transfer Piping  

SciTech Connect

Heat transfer studies were made to determine the thermal characteristics of double-shell tank transfer piping under both transient and steady-state conditions. A number of design and operation options were evaluated for this piping system which is in its early design phase.

HECHT, S.L.

2000-02-15T23:59:59.000Z

342

Convective heat transfer inside passive solar buildings  

DOE Green Energy (OSTI)

Natural convection between spaces in a building can play a major role in energy transfer. Two situations are investigated: convection through a single doorway into a remote room, and a convective loop in a two-story house with a south sunspace where a north stairway serves as the return path. A doorway-sizing equation is given for the single-door case. Detailed data are given from the monitoring of airflow in one two-story house and summary data are given for five others. Observations on the nature of the airflow and design guidelines are presented.

Jones, R.W.; Balcomb, J.D.; Yamaguchi, K.

1983-01-01T23:59:59.000Z

343

THERM: Two-Dimensional Building Heat-Transfer Modeling  

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

5 5 THERM: Two-Dimensional Building Heat-Transfer Modeling For more information and to download THERM, please visit our website: http://windows.lbl.gov/software/therm The Windows and Daylighting Group's two-year-old computer program THERM 1.0 is a state-of-the-art tool for modeling two-dimensional heat-transfer effects in building components. The thermal property information THERM provides is important for the design and application of building components such as windows, walls, foundations, roofs and doors. This Microsoft Windows-based program has great potential to users such as building component manufacturers, educators, students, architects, engineers and others who are interested in assessing the heat-transfer properties of single products, product interactions, or integrated systems. THERM

344

Heat Transfer in Projecting and Sloped Fenestration Products  

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

Heat Transfer in Projecting and Sloped Fenestration Products Heat Transfer in Projecting and Sloped Fenestration Products Speaker(s): Dragan Charlie Curcija Date: May 26, 2010 - 12:00pm Location: 90-3122 The heat transfer performance of fenestration products is routinely determined using computer simulations combined with physical testing. Initial efforts to develop simulation and test procedures for the fenestration products in the 1980's focused on simple planar windows since they are the dominant share of the market. However, once these procedures were developed (with resulting ISO standards and national rating and labeling requirements), manufacturers of more physically complex fenestration products (skylights, green house windows, tubular skylights) demanded procedures for simulating and testing their products. Dr Curcija

345

MODELING OF HEAT TRANSFER IN ROOMS IN THE MODELICA  

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

MODELING MODELING OF HEAT TRANSFER IN ROOMS IN THE MODELICA "BUILDINGS" LIBRARY Michael Wetter, Wangda Zuo, Thierry Stephane Nouidui Simulation Research Group, Building Technologies Department Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory Berkeley, CA 94720, USA ABSTRACT This paper describes the implementation of the room heat transfer model in the free open-source Modelica "Buildings" library. The model can be used as a single room or to compose a multizone building model. We discuss how the model is de- composed into submodels for the individual heat transfer phenomena. We also discuss the main physical assumptions. The room model can be parameterized to use di↵erent modeling assump- tions, leading to linear or non-linear di↵erential algebraic systems of equations. We present nu- merical experiments that show

346

FEHM: finite element heat and mass transfer code  

DOE Green Energy (OSTI)

The finite element heat and mass (FEHM) transfer code is a computer code developed to simulate geothermal and hot dry rock reservoirs. It is also applicable to natural-state studies of geothermal systems and ground-water flow. It solves the equations of heat and mass transfer for multiphase flow in porous and permeable media using the finite element method. The code also has provisions for a noncoupled tracer; that is, the tracer solutions do not affect the heat and mass transfer solutions. It can simulate two-dimensional, two-dimensional radial, or three-dimensional geometries. A summary of the equations in the model, the numerical solution procedure, and model verification and validation are provided in this report. A user's guide and sample problems are included in the appendices. 17 refs., 10 figs., 4 tabs.

Zyvoloski, G.; Dash, Z.; Kelkar, S.

1988-03-01T23:59:59.000Z

347

Heat and mass transfer analysis of a desiccant dehumidifier matrix  

DOE Green Energy (OSTI)

This report documents the SERI Single-Blow Test Facility's design, fabrication, and testing for characterizing desiccant dehumidifiers for solar cooling applications. The first test article, a silica-gel parallel-plate dehumidifier with highly uniform passages, was designed and fabricated. Transient heat and mass transfer data and pressure drop data across the dehumidifier were obtained. Available heat and mass transfer models were extended to the parallel-place geometry, and the experimental data were compared with model predictions. Pressure drop measurements were also compared with model predictions of the fully developed laminar flow theory. The comparisons between the lumped-capacitance model and the experimental data were satisfactory. The pressure drop data compared satisfactorily with the theory (within 15%). A solid-side resistance model that is more detailed and does not assume symmetrical diffusion in particles was recommended for performance. This study has increased our understanding of the heat and mass transfer in silica gel parallel-plate dehumidifiers.

Pesaran, A.A.

1986-07-01T23:59:59.000Z

348

A 2-D Test Problem for CFD Modeling Heat Transfer in Spent Fuel Transfer Cask Neutron Shields  

SciTech Connect

In the United States, commercial spent nuclear fuel is typically moved from spent fuel pools to outdoor dry storage pads within a transfer cask system that provides radiation shielding to protect personnel and the surrounding environment. The transfer casks are cylindrical steel enclosures with integral gamma and neutron radiation shields. Since the transfer cask system must be passively cooled, decay heat removal from spent nuclear fuel canister is limited by the rate of heat transfer through the cask components, and natural convection from the transfer cask surface. The primary mode of heat transfer within the transfer cask system is conduction, but some cask designs incorporate a liquid neutron shield tank surrounding the transfer cask structural shell. In these systems, accurate prediction of natural convection within the neutron shield tank is an important part of assessing the overall thermal performance of the transfer cask system. The large-scale geometry of the neutron shield tank, which is typically an annulus approximately 2 meters in diameter but only 5-10 cm in thickness, and the relatively small scale velocities (typically less than 5 cm/s) represent a wide range of spatial and temporal scales that contribute to making this a challenging problem for computational fluid dynamics (CFD) modeling. Relevant experimental data at these scales are not available in the literature, but some recent modeling studies offer insights into numerical issues and solutions; however, the geometries in these studies, and for the experimental data in the literature at smaller scales, all have large annular gaps that are not prototypic of the transfer cask neutron shield. This paper presents results for a simple 2-D problem that is an effective numerical analog for the neutron shield application. Because it is 2-D, solutions can be obtained relatively quickly allowing a comparison and assessment of sensitivity to model parameter changes. Turbulence models are considered as well as the tradeoff between steady state and transient solutions. Solutions are compared for two commercial CFD codes, FLUENT and STAR-CCM+. The results can be used to provide input to the CFD Best Practices for this application. Following study results for the 2-D test problem, a comparison of simulation results is provided for a high Rayleigh number experiment with large annular gap. Because the geometry of this validation is significantly different from the neutron shield, and due to the critical nature of this application, the argument is made for new experiments at representative scales

Zigh, Ghani; Solis, Jorge; Fort, James A.

2011-01-14T23:59:59.000Z

349

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures  

E-Print Network (OSTI)

Heat Transfer Using Micro/Nano Structures by Ming-Chang Lu AHeat Transfer Using Micro/Nano Structures Copyright 2010 byHeat Transfer Using Micro/Nano Structures by Ming-Chang Lu

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

350

Low heat transfer, high strength window materials  

DOE Patents (OSTI)

A multi-pane window with improved insulating qualities; comprising a plurality of transparent or translucent panes held in an essentially parallel, spaced-apart relationship by a frame. Between at least one pair of panes is a convection defeating means comprising an array of parallel slats or cells so designed as to prevent convection currents from developing in the space between the two panes. The convection defeating structures may have reflective surfaces so as to improve the collection and transmittance of the incident radiant energy. These same means may be used to control (increase or decrease) the transmittance of solar energy as well as to decouple the radiative transfer between the interior surfaces of the transparent panes.

Berlad, Abraham L. (Stony Brook, NY); Salzano, Francis J. (Patchogue, NY); Batey, John E. (Stony Brook, NY)

1978-01-01T23:59:59.000Z

351

Heat transfer education : Keeping it relevant and vibrant.  

SciTech Connect

The motivation for a fresh look at heat transfer education, both in content and in methodology, is generated by a number of trends in engineering practice. These include the increasing demand for engineers with interdisciplinary skills, rapid integration of technology, emergence of computerized and interactive problem-solving tools, shortening time of concept-to-market, availability of new technologies, and an increasing number of new or redesigned products and processes in which heat transfer plays a part. Examination of heat transfer education in this context can be aided by considering the changes, both qualitatively and quantitatively, in the student, educator, and researcher populations, employment opportunities, in the needs of corporations, government, industry, and universities, and in the relevant technical problems and issues of the day. Such an overview provides the necessary background for charting a response to the difficult question of how to maintain excellence and continuity in heat transfer education in the face of rapid, widespread, and complex changes. The present paper addresses how to make heat transfer education more relevant and stimulating. This paper represents a written summary of a 1996 panel discussion at the 1996 International Mechanical Engineering Conference and Exhibition (IMECE) of the American Society of Mechanical Engineers (ASME) in Atlanta, Georgia, on ''Heat Transfer Education: Keeping it Relevant and Vibrant,'' with significant expansion and amplification by the authors and the panelists in the 1997-98 period. The consensus of the participants is that the steps necessary to ensure the desired outcome in heat transfer education should include: (1) a better understanding of the interaction between the student, course content, and market needs; (2) an appreciation of the need in multidisciplinary industrial environments for engineers trained with a broad background: (3) a revision of the introductory heat transfer course to incorporate illustrative and insightful industrial examples and case studies reducible to order-of-magnitude analyses; (4) a reinforcement of real-world problem-solving abilities in students by introducing them to examples that emphasize multidisciplinary issues in modern thermal management problems and finally (5) industrial collaboration that would provide the educator with meaningful thermal management case studies (and possible funding), the student with an appreciation of industrial practices, and the industrial sponsor with access to academia for assistance in problem solving. Also suggested is an effective regular review program to provide assessment, feedback, and suggestions for quality control to interested institutions on their teaching methodology and materials.

Khounsary, A. M.

1998-08-14T23:59:59.000Z

352

Advanced multistage turbine blade aerodynamics, performance, cooling, and heat transfer  

DOE Green Energy (OSTI)

The gas turbine has the potential for power production at the highest possible efficiency. The challenge is to ensure that gas turbines operate at the optimum efficiency so as to use the least fuel and produce minimum emissions. A key component to meeting this challenge is the turbine. Turbine performance, both aerodynamics and heat transfer, is one of the barrier advanced gas turbine development technologies. This is a result of the complex, highly three-dimensional and unsteady flow phenomena in the turbine. Improved turbine aerodynamic performance has been achieved with three-dimensional highly-loaded airfoil designs, accomplished utilizing Euler or Navier-Stokes Computational Fluid Dynamics (CFD) codes. These design codes consider steady flow through isolated blade rows. Thus they do not account for unsteady flow effects. However, unsteady flow effects have a significant impact on performance. Also, CFD codes predict the complete flow field. The experimental verification of these codes has traditionally been accomplished with point data - not corresponding plane field measurements. Thus, although advanced CFD predictions of the highly complex and three-dimensional turbine flow fields are available, corresponding data are not. To improve the design capability for high temperature turbines, a detailed understanding of the highly unsteady and three-dimensional flow through multi-stage turbines is necessary. Thus, unique data are required which quantify the unsteady three-dimensional flow through multi-stage turbine blade rows, including the effect of the film coolant flow. Also, as design CFD codes do not account for unsteady flow effects, the next logical challenge and the current thrust in CFD code development is multiple-stage analyses that account for the interactions between neighboring blade rows. Again, to verify and or direct the development of these advanced codes, complete three-dimensional unsteady flow field data are needed.

Fleeter, S.; Lawless, P.B. [Purdue Univ., West Lafayette, IN (United States). School of Mechanical Engineering

1995-12-31T23:59:59.000Z

353

Enhancement and suppression of heat transfer by MHD turbulence  

E-Print Network (OSTI)

We study of the effect of turbulence on heat transfer within magnetized plasmas for energy injection velocities both larger and smaller that the Alfven speed. We find that in the latter regime the heat transfer is partially suppressed, while in the former regime the effects of turbulence depend on the intensity of driving. In fact, the scale l at which the turbulent velocity is equal the Alfven velocity is a new important parameter. When the electron mean free path is larger than l, the stronger the the turbulence, the lower thermal conductivity by electrons is. The turbulent motions, however, induces their own advective heat transport, which, for the parameters of intracluster medium (ICM) provides effective heat diffusivity that exceeds the classical Spitzer value.

A. Lazarian

2006-08-02T23:59:59.000Z

354

Combined heat and mass transfer device for improving separation process  

DOE Patents (OSTI)

A two-phase small channel heat exchange matrix simultaneously provides for heat transfer and mass transfer between the liquid and vapor phases of a multi-component mixture at a single, predetermined location within a separation column, significantly improving the thermodynamic efficiency of the separation process. The small channel heat exchange matrix is composed of a series of channels having a hydraulic diameter no greater than 5.0 millimeters for conducting a two-phase coolant. In operation, the matrix provides the liquid-vapor contacting surfaces within the separation column, such that heat and mass are transferred simultaneously between the liquid and vapor phases. The two-phase coolant allows for a uniform heat transfer coefficient to be maintained along the length of the channels and across the surface of the matrix. Preferably, a perforated, concave sheet connects each channel to an adjacent channel to facilitate the flow of the liquid and vapor phases within the column and to increase the liquid-vapor contacting surface area.

Tran, Thanh Nhon (Flossmoor, IL)

1999-01-01T23:59:59.000Z

355

Combined heat and mass transfer device for improving separation process  

DOE Patents (OSTI)

A two-phase small channel heat exchange matrix simultaneously provides for heat transfer and mass transfer between the liquid and vapor phases of a multi-component mixture at a single, predetermined location within a separation column, significantly improving the thermodynamic efficiency of the separation process. The small channel heat exchange matrix is composed of a series of channels having a hydraulic diameter no greater than 5.0 millimeters for conducting a two-phase coolant. In operation, the matrix provides the liquid-vapor contacting surfaces within the separation column, such that heat and mass are transferred simultaneously between the liquid and vapor phases. The two-phase coolant allows for a uniform heat transfer coefficient to be maintained along the length of the channels and across the surface of the matrix. Preferably, a perforated, concave sheet connects each channel to an adjacent channel to facilitate the flow of the liquid and vapor phases within the column and to increase the liquid-vapor contacting surface area. 12 figs.

Tran, T.N.

1999-08-24T23:59:59.000Z

356

Dynamic van der Waals Theory of Two-Phase Fluids in Heat Flow Akira Onuki  

E-Print Network (OSTI)

Dynamic van der Waals Theory of Two-Phase Fluids in Heat Flow Akira Onuki Department of Physics as a functional of the order parameter and the energy density. Let us consider one-component fluids, where-component fluids the effect is drastically altered due to latent heat generation or absorption at the interface [12

357

Waste Heat Recovery by Organic Fluid Rankine Cycle  

E-Print Network (OSTI)

The use of Organic Rankine Cycle for waste heat recovery presents several characteristics which are analyzed in details. After a short comparison with steam cycles, the Organic Rankine Cycle is described : its simplicity is shown and achievable efficiencies versus heat source temperature are given. Available fluids are presented. The choice of the fluid allows a good adaptation to temperature and power for each application. The most interesting field for Organic Rankine Cycles are low mechanical powers of a few megawatts and medium temperatures, about 500 C/600 C, for flue gas. The very simple technology of turbines is shown. Three examples are presented. The first one is a test loop of 300 thermal kW built in BERTIN & Cie laboratory to experiment a supersonic turbine designed by the same company for organic vapor at 250 C. The second gives the main characteristics of recovery from exhaust gas of Diesel engines. The last deals with possible recovery from air quenching of clinker in cement plants.

Verneau, A.

1979-01-01T23:59:59.000Z

358

Enhanced heat transfer with metal wool filled tubes  

SciTech Connect

The Advanced Photon Source (APS) to be constructed at Argonne National Laboratory (ANL) utilizes magnetic devices which generate x-ray beams with very intense heat flux levels. The flux levels encountered can be one or two orders of magnitude higher than those commonly found in nuclear reactors or fusion devices. The beam line elements and optics on such beams pose significant challenge to the researchers and designers to keep them cooled at acceptable levels of surface temperature and/or temperature gradients. Therefore, methods and techniques achieving heat removal enhancement are constantly sought. One such technique suggested and considered is the use of conductive metal wool filled tubes where the filter is brazed to the tube walls. A comparative investigation of the conventionally achievable heat transfer coefficient h'' with water and the wall conductance of a heavy wall copper tube reveals that major resistance is on the coolant side. Therefore, there exists a significant opportunity to improve heat transfer in the tubes by enhancement of the coolant side. To this end a variety of copper wool filled tubes as well as a commercially available enhanced copper tube were subjected to laboratory tests with water and conventional heating to assess the resulting heat transfer improvement. Design improvements using enhanced cooling are discussed in terms of structural weight, controls, grazing angles, the operational reliability. 9 refs., 11 figs., 5 tabs.

Kuzay, T.M.; Collins, J.T.; Khounsary, A.M. (Argonne National Lab., IL (USA)); Morales, G. (Argonne National Lab., IL (USA) Texas Univ., El Paso, TX (USA))

1990-08-01T23:59:59.000Z

359

Trace formulae for non-equilibrium Casimir interactions, heat radiation and heat transfer for arbitrary objects  

E-Print Network (OSTI)

We present a detailed derivation of heat radiation, heat transfer and (Casimir) interactions for N arbitrary objects in the framework of fluctuational electrodynamics in thermal non-equilibrium. The results can be expressed as basis-independent trace formulae in terms of the scattering operators of the individual objects. We prove that heat radiation of a single object is positive, and that heat transfer (for two arbitrary passive objects) is from the hotter to a colder body. The heat transferred is also symmetric, exactly reversed if the two temperatures are exchanged. Introducing partial wave-expansions, we transform the results for radiation, transfer and forces into traces of matrices that can be evaluated in any basis, analogous to the equilibrium Casimir force. The method is illustrated by (re)deriving the heat radiation of a plate, a sphere and a cylinder. We analyze the radiation of a sphere for different materials, emphasizing that a simplification often employed for metallic nano-spheres is typically invalid. We derive asymptotic formulae for heat transfer and non-equilibrium interactions for the cases of a sphere in front a plate and for two spheres, extending previous results. As an example, we show that a hot nano-sphere can levitate above a plate with the repulsive non-equilibrium force overcoming gravity -- an effect that is not due to radiation pressure.

Matthias Krüger; Giuseppe Bimonte; Thorsten Emig; Mehran Kardar

2012-07-02T23:59:59.000Z

360

Enhanced heat transfer surface for cast-in-bump-covered cooling surfaces and methods of enhancing heat transfer  

DOE Patents (OSTI)

An annular turbine shroud separates a hot gas path from a cooling plenum containing a cooling medium. Bumps are cast in the surface on the cooling side of the shroud. A surface coating overlies the cooling side surface of the shroud, including the bumps, and contains cooling enhancement material. The surface area ratio of the cooling side of the shroud with the bumps and coating is in excess of a surface area ratio of the cooling side surface with bumps without the coating to afford increased heat transfer across the element relative to the heat transfer across the element without the coating.

Chiu, Rong-Shi Paul (Glenmont, NY); Hasz, Wayne Charles (Pownal, VT); Johnson, Robert Alan (Simpsonville, SC); Lee, Ching-Pang (Cincinnati, OH); Abuaf, Nesim (Lincoln City, OR)

2002-01-01T23:59:59.000Z

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


361

Method of measuring heat influx of a cryogenic transfer system  

DOE Patents (OSTI)

A method is provided for measuring the heat influx of a cryogenic transfer system. A gaseous phase of the cryogen used during normal operation of the system is passed through the system. The gaseous cryogen at the inlet to the system is tempered to duplicate the normal operating temperature of the system inlet. The temperature and mass flow rate of the gaseous cryogen is measured at the outlet of the system, and the heat capacity of the cryogen is determined. The heat influx of the system is then determined from known thermodynamic relationships.

Niemann, Ralph C. (Downers Grove, IL); Zelipsky, Steven A. (Tinley Park, IL); Rezmer, Ronald R. (Lisle, IL); Smelser, Peter (Bruner, MO)

1981-01-01T23:59:59.000Z

362

Development of a Heat Transfer Model for the Integrated Facade Heating  

E-Print Network (OSTI)

Façade heating is a special application of radiant heating and cooling technology and is used to enhance the indoor comfort level of offices, hotels and museums. Mullion radiators are typically used to implement façade heating. This paper analyzes the heat transfer process of facade heating (mullion radiators) in a pilot research project in Pittsburgh, PA. The heat transfer model for facade heating is developed and verified by measured data. The comparison shows that the heat transfer model predicts the measured temperatures with a root mean squared error (RMSE) of the hot water return temperature, the mullion surface temperature, and the window surface temperature of 0.90°F, 0.98°F and 1.15°F, respectively. The factors which affect the heating capacity of mullion radiators have been analyzed. The analysis shows that the supply water temperature is the primary factor which affects the heating or cooing capacity of window mullions and the mullion surface temperature. Return water temperature and mullion surface temperature are quasi-linear functions often water supply temperature. Mullion surface temperature, indoor air temperature gradient on the glazing surface within one foot from mullions is much higher than in the central part of the window. The temperatures in the central 2 feet of a 4-foot window show almost no influence by the mullion surface temperature. Also, the conductive thermal resistance of the mullion double tubes with fillings between two tubes plays a decisive role in controlling the mullion and window frame temperatures.

Gong, X.; Archer, D. H.; Claridge, D. E.

2007-01-01T23:59:59.000Z

363

Investigation of Enhanced Heat Transfer Coefficient with an Electrostatic Grid  

Science Conference Proceedings (OSTI)

Some major contributors to efficiency loss in a fossil or nuclear plant are associated with nucleation of moisture from superheated steam, formation and release of liquid films on turbine surfaces, and the flow and condensation of moist steam into the turbine exhaust and condenser. This report investigates the possible effect of an electrostatic charge on these processes and therefore on heat transfer.

2004-09-15T23:59:59.000Z

364

A mesoscopic description of radiative heat transfer at the nanoscale  

E-Print Network (OSTI)

We present a formulation of the nanoscale radiative heat transfer (RHT) using concepts of mesoscopic physics. We introduce the analog of the Sharvin conductance using the quantum of thermal conductance. The formalism provides a convenient framework to analyse the physics of RHT at the nanoscale. Finally, we propose a RHT experiment in the regime of quantized conductance.

Svend-Age Biehs; Emmanuel Rousseau; Jean-Jacques Greffet

2011-03-11T23:59:59.000Z

365

Integration of Heat Transfer, Stress, and Particle Trajectory Simulation  

Science Conference Proceedings (OSTI)

Calabazas Creek Research, Inc. developed and currently markets Beam Optics Analyzer (BOA) in the United States and abroad. BOA is a 3D, charged particle optics code that solves the electric and magnetic fields with and without the presence of particles. It includes automatic and adaptive meshing to resolve spatial scales ranging from a few millimeters to meters. It is fully integrated with CAD packages, such as SolidWorks, allowing seamless geometry updates. The code includes iterative procedures for optimization, including a fully functional, graphical user interface. Recently, time dependent, particle in cell capability was added, pushing particles synchronically under quasistatic electromagnetic fields to obtain particle bunching under RF conditions. A heat transfer solver was added during this Phase I program. Completed tasks include: (1) Added a 3D finite element heat transfer solver with adaptivity; (2) Determined the accuracy of the linear heat transfer field solver to provide the basis for development of higher order solvers in Phase II; (3) Provided more accurate and smoother power density fields; and (4) Defined the geometry using the same CAD model, while maintaining different meshes, and interfacing the power density field between the particle simulator and heat transfer solvers. These objectives were achieved using modern programming techniques and algorithms. All programming was in C++ and parallelization in OpenMP, utilizing state-of-the-art multi-core technology. Both x86 and x64 versions are supported. The GUI design and implementation used Microsoft Foundation Class.

Thuc Bui; Michael Read; Lawrence ives

2012-05-17T23:59:59.000Z

366

Heat transfer in inertial confinement fusion reactor systems  

SciTech Connect

The short time and deposition distance for the energy from inertial fusion products results in local peak power densities on the order of 10/sup 18/ watts/m/sup 3/. This paper presents an overview of the various inertial fusion reactor designs which attempt to reduce these peak power intensities and describes the heat transfer considerations for each design.

Hovingh, J.

1980-04-23T23:59:59.000Z

367

Combined heat and mass transfer device for improving separation process  

DOE Patents (OSTI)

A two-phase small channel heat exchange matrix for providing simultaneous heat transfer and mass transfer at a single, predetermined location within a separation column, whereby the thermodynamic efficiency of the separation process is significantly improved. The small channel heat exchange matrix is comprised of a series of channels having a hydraulic diameter no greater than 5.0 mm. The channels are connected to an inlet header for supplying a two-phase coolant to the channels and an outlet header for receiving the coolant horn the channels. In operation, the matrix provides the liquid-vapor contacting surfaces within a separation column, whereby liquid descends along the exterior surfaces of the cooling channels and vapor ascends between adjacent channels within the matrix. Preferably, a perforated and concave sheet connects each channel to an adjacent channel, such that liquid further descends along the concave surfaces of the sheets and the vapor further ascends through the perforations in the sheets. The size and configuration of the small channel heat exchange matrix allows the heat and mass transfer device to be positioned within the separation column, thereby allowing precise control of the local operating conditions within the column and increasing the energy efficiency of the process.

Tran, Thanh Nhon

1997-12-01T23:59:59.000Z

368

Thermodynamics of enhanced heat transfer: a model study  

E-Print Network (OSTI)

Situations where a spontaneous process of energy or matter transfer is enhanced by an external device are widespread in nature (human sweating system, enzyme catalysis, facilitated diffusion across bio-membranes, industrial heat exchangers). The thermodynamics of such processes remains however open. Here we study enhanced heat transfer by a model junction immersed between two thermal baths at different temperatures $T_h$ and $T_c$ ($T_h>T_c$). The transferred heat power is enhanced via controlling the junction by means of external time-dependent fields. Provided that the spontaneous heat flow process is optimized over the junction Hamiltonian, any enhancement of this spontaneous process does demand consumption and subsequent dissipation of work. The efficiency of enhancement is defined via the increment in the heat power divided over the amount of consumed work. We show that this efficiency is bounded from above by $T_c/(T_h-T_c)$. Formally this is identical to the Carnot bound for the efficiency of ordinary ...

Hovhannisyan, Karen; 10.1088/1742-5468/2010/06/P06010

2010-01-01T23:59:59.000Z

369

Heat transfer characteristics of a surface type direct contact boiler  

DOE Green Energy (OSTI)

Two direct contact heat exchangers were constructed and test results were obtained using water and refrigerant 113 as the working fluids. The heat exchangers were operated in a three-phase mode; the water remained liquid throughout the vessel and the liquid refrigerant 113 underwent vaporization following direct injection into the water. The effect of important operational parameters--operating heights, refrigerant 113 injection techniques, mass flow ratios, and temperatures--was studied to determine generalized trends important in the design and operation of a prototype three-phase direct contact heat exchanger. The primary system used in this study performed well overall. The initial favorable results of this study warrant further investigation of direct contact heat exchange as a means of utilizing geothermal energy.

Deeds, R.S.; Jacobs, H.R.; Boehm, R.F.

1976-03-01T23:59:59.000Z

370

Estimation of heat transfer in oscillating annular flow using artifical neural networks  

Science Conference Proceedings (OSTI)

In this study, the prediction of heat transfer from a surface having constant heat flux subjected to oscillating annular flow is investigated using artificial neural networks (ANNs). An experimental study is carried out to estimate the heat transfer ... Keywords: Annular duct, Artificial neural network, Heat transfer, Oscillating flow

Unal Akdag; M. Aydin Komur; A. Feridun Ozguc

2009-09-01T23:59:59.000Z

371

Mixed-convective, conjugate heat transfer during molten salt quenching of small parts  

Science Conference Proceedings (OSTI)

It is common in free quenching immersion heat treatment calculations to locally apply constant or surface-averaged heat-transfer coefficients obtained from either free or forced steady convection over simple shapes with small temperature differences from the ambient fluid. This procedure avoids the solution of highly transient, non-Boussinesq conjugate heat transfer problems which often involve mixed convection, but it leaves great uncertainty about the general adequacy of the results. In this paper we demonstrate for small parts (dimensions of the order of inches rather than feet) quenched in molten salt, that it is feasible to calculate such nonuniform surface heat transfer from first principles without adjustable empirical parameters. We use literature physical property salt data from the separate publications of Kirst et al., Nissen, Carling, and Teja, et al. for T800 F is not considered to be important due to the short time the surface temperature exceeds that value for small parts. Similarly, for small parts, the local Reynolds and Rayleigh numbers are below the corresponding critical values for most if not all of the quench, so that we see no evidence of the existence of significant turbulence effects, only some large scale unsteadiness for brief periods. The experimental data comparisons from the open literature include some probe cooling-rate results of Foreman, as well as some cylinder thermal histories of Howes.

Chenoweth, D.R.

1997-02-01T23:59:59.000Z

372

Mixed-convective, conjugate heat transfer during molten salt quenching of small parts  

SciTech Connect

It is common in free quenching immersion heat treatment calculations to locally apply constant or surface-averaged heat-transfer coefficients obtained from either free or forced steady convection over simple shapes with small temperature differences from the ambient fluid. This procedure avoids the solution of highly transient, non-Boussinesq conjugate heat transfer problems which often involve mixed convection, but it leaves great uncertainty about the general adequacy of the results. In this paper we demonstrate for small parts (dimensions of the order of inches rather than feet) quenched in molten salt, that it is feasible to calculate such nonuniform surface heat transfer from first principles without adjustable empirical parameters. We use literature physical property salt data from the separate publications of Kirst et al., Nissen, Carling, and Teja, et al. for T<1000 F, and then extrapolate it to the initial part temperature. The reported thermal/chemical breakdown of NaNO{sub 2} for T>800 F is not considered to be important due to the short time the surface temperature exceeds that value for small parts. Similarly, for small parts, the local Reynolds and Rayleigh numbers are below the corresponding critical values for most if not all of the quench, so that we see no evidence of the existence of significant turbulence effects, only some large scale unsteadiness for brief periods. The experimental data comparisons from the open literature include some probe cooling-rate results of Foreman, as well as some cylinder thermal histories of Howes.

Chenoweth, D.R.

1997-02-01T23:59:59.000Z

373

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

Open Energy Info (EERE)

repository. The modeling approach is based on a mathematical formulation of coupled multiphase, multicomponent fluid and heat flow through porous and fractured rock. Fracture...

374

ADVANCES IN MODELING OF GROUND-SOURCE HEAT  

E-Print Network (OSTI)

] K. C. Toh, X. Y. Chen, and J. C. Chai, "Numerical computation of fluid flow and heat transfer journal and conference papers. His current research interests include heat transfer and fluid-flow to substantially increase the heat transfer coefficient when a fluid is passing through microchannels. Heat sinks

375

Influence of Infrared Radiation on Attic Heat Transfer  

E-Print Network (OSTI)

An experimental study concerned with different modes of heal transfer in fibrous and cellulose insulating material is presented. A series of experiments were conducted using an attic simulator to determine the effects of ventilation on attic heat transfer, and the effect of infrared radiation on the thermal conductivity of the insulation system and on attic heat transfer. All the tests were performed at steady state conditions by controlling the roof deck temperature. Calculations are performed for insulation thicknesses between 1 inch (2.54cm) and 6.0 inches (15.24cm) and roof deck temperatures between 145°F (62.78°C) and 100°F (36.78°C). The temperature profiles within the insulation were measured by placing thermocouples at various levels within the insulation. The profiles for the cellulose insulation are linear. The profiles within the glass fiber insulation are non-linear due to the effect of infrared radiation. Also heat fluxes were measured through different insulation thicknesses and for different roof temperatures. It was found that a radiant barrier such as aluminum foil can reduce the heat flux significantly. Experimental results were compared to a Three-Region approximate solution developed at Oak Ridge National Laboratories (ORNL). The model was in good agreement with experimental results.

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

1985-01-01T23:59:59.000Z

376

Group Velocity and the Linear Response of Stratified Fluids to Internal Heat or Mass Sources  

Science Conference Proceedings (OSTI)

A steadily maintained line heat or mass source turned on in an unbounded, steadily moving, uniformly stratified flow will in general create ever-increasing vertical displacements of the fluid. Lin and Smith viewed a maintained heat source as a ...

Chris Bretherton

1988-01-01T23:59:59.000Z

377

Heat transfer and hydrodynamics analysis of a novel dimpled tube  

SciTech Connect

In the present investigation, heat transfer and hydrodynamics analysis of a new enhanced heat transfer tube with ellipsoidal dimples was carried out. The dimples are disposed to form a certain specified angle between the major axis of the ellipsoid and flow direction, and the direction of the major axis of each adjacent ellipsoidal dimple in the same cross-section is alternated. Experimental tests were carried out with heating water on the shell side with a constant flow rate, and cold air in the tube side with flow rates range from 1 to 55 m{sup 3}/h. The temperatures and pressures for the inlet and outlet of both sides were measured. The heat transfer and pressure drop of the new dimpled tube were investigated and compared with the results of a dimpled tube with spherical dimples and a conventional smooth tube. The computed results indicated that the Nusselt number for ellipsoidal dimpled tube and spherical dimpled tube are 38.6-175.1% and 34.1-158% higher than that for the smooth tube respectively. The friction factors of dimpled tube increase by 26.9-75% and 32.9-92% for ellipsoidal and spherical dimples compared with the smooth tube respectively. It was perceived that ellipsoidal dimple roughness accelerates transition to critical Reynolds numbers down to less than 1000. By integrated performance evaluation of (Nu{sub a}/Nu{sub s})/(f{sub a}/f{sub s}), a maximum of about 87% heat transfer enhancement with the same friction penalty could be achieved by optimize the dimpled tube design. (author)

Wang, Yu.; He, Ya-Ling; Lei, Yong-Gang; Zhang, Jie [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049 (China)

2010-11-15T23:59:59.000Z

378

Simulation of a Heat Transfer in Porous Media  

E-Print Network (OSTI)

We are motivated to model a heat transfer to a multiple layer regime and their optimization for heat energy resources. Such a problem can be modeled by a porous media with different phases (liquid and solid). The idea arose of a geothermal energy reservoir which can be used by cities, e.g. Berlin. While hot ground areas are covered to most high populated cites, the energy resources are important and a shift to use such resources are enormous. We design a model of the heat transport via the flow of water through the heterogeneous layer of the underlying earth sediments. We discuss a multiple layer model, based on mobile and immobile zones. Such numerical simulations help to economize on expensive physical experiments and obtain control mechanisms for the delicate heating process.

Juergen Geiser

2012-05-11T23:59:59.000Z

379

Survey of technology for storage of thermal energy in heat transfer salt  

DOE Green Energy (OSTI)

The widespread use of nitrate-based fused salt mixtures as heat transport media in the petroleum and chemical process industries and in metallurgical heat-treatment operations has led to the development of satisfactory equipment for handling and containing these materials. A mixture known as heat transfer salt (HTS), which is composed of 40 percent NaNO/sub 2/, 7 percent NaNO/sub 3/, and 53 percent KNO/sub 3/ by weight, has been used commercially in large quantities as a heat transfer fluid. It has been suggested that this salt be used for storing energy as sensible heat in the temperature range 200 to 540/sup 0/C (400 to 1000/sup 0/F). The eutectic 54 percent KNO/sub 3/--46 percent NaNO/sub 3/ by weight known as ''draw salt,'' which has undergone less testing but is more stable thermally and more attractive economically than HTS and has similar physical properties, may be a desirable alternative. Several specific energy storage applications, such as intermediate-load and peaking electric power, solar energy, and energy from fluidized-bed coal burners, are discussed. Long-term stability and corrosion data on these salts are presently available only to approximately 480/sup 0/C. However, for the design and construction of energy storage facilities to operate over many years at temperatures up to approximately 540/sup 0/C, long-term tests of thermal stability and corrosion are needed. Means for obtaining such information are proposed.

Silverman, M.D.; Engel, J.R.

1977-01-18T23:59:59.000Z

380

A Reduced-Boundary-Function Method for Convective Heat Transfer With Axial Heat Conduction and Viscous Dissipation  

Science Conference Proceedings (OSTI)

We introduce a new method of solution for the convective heat transfer under forced laminar flow that is confined by two parallel plates with a distance of 2a or by a circular tube with a radius of a. The advection-conduction equation is first mapped onto the boundary. The original problem of solving the unknown field T(x,r,t) is reduced to seek the solutions of T at the boundary (r = a or r = 0, r is the distance from the centerline shown in Fig. 1), i.e., the boundary functions T{sub a}(x,t) {triple_bond} T(x,r=a,t) and/or T{sub 0}(x,t) {triple_bond} T(x,r=0,t). In this manner, the original problem is significantly simplified by reducing the problem dimensionality from 3 to 2. The unknown field T(x,r,t) can be eventually solved in terms of these boundary functions. The method is applied to the convective heat transfer with uniform wall temperature boundary condition and with heat exchange between flowing fluids and its surroundings that is relevant to the geothermal applications. Analytical solutions are presented and validated for the steady-state problem using the proposed method.

Zhijie Xu

2012-07-01T23:59:59.000Z

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


381

A Reduced-Boundary-Function Method for Convective Heat Transfer with Axial Heat Conduction and Viscous Dissipation  

Science Conference Proceedings (OSTI)

We introduce a method of solution for the convective heat transfer under forced laminar flow that is confined by two parallel plates with a distance of 2a or by a circular tube with a radius of a. The advection-conduction equation is first mapped onto the boundary. The original problem of solving the unknown field is reduced to seek the solutions of T at the boundary (r=a or r=0, r is the distance from the centerline shown in Fig. 1), i.e. the boundary functions and/or . In this manner, the original problem is significantly simplified by reducing the problem dimensionality from 3 to 2. The unknown field can be eventually solved in terms of these boundary functions. The method is applied to the convective heat transfer with uniform wall temperature boundary condition and with heat exchange between flowing fluids and its surroundings that is relevant to the geothermal applications. Analytical solutions are presented and validated for the steady state problem using the proposed method.

Xu, Zhijie

2012-07-01T23:59:59.000Z

382

Transient PVT measurements and model predictions for vessel heat transfer. Part II.  

SciTech Connect

Part I of this report focused on the acquisition and presentation of transient PVT data sets that can be used to validate gas transfer models. Here in Part II we focus primarily on describing models and validating these models using the data sets. Our models are intended to describe the high speed transport of compressible gases in arbitrary arrangements of vessels, tubing, valving and flow branches. Our models fall into three categories: (1) network flow models in which flow paths are modeled as one-dimensional flow and vessels are modeled as single control volumes, (2) CFD (Computational Fluid Dynamics) models in which flow in and between vessels is modeled in three dimensions and (3) coupled network/CFD models in which vessels are modeled using CFD and flows between vessels are modeled using a network flow code. In our work we utilized NETFLOW as our network flow code and FUEGO for our CFD code. Since network flow models lack three-dimensional resolution, correlations for heat transfer and tube frictional pressure drop are required to resolve important physics not being captured by the model. Here we describe how vessel heat transfer correlations were improved using the data and present direct model-data comparisons for all tests documented in Part I. Our results show that our network flow models have been substantially improved. The CFD modeling presented here describes the complex nature of vessel heat transfer and for the first time demonstrates that flow and heat transfer in vessels can be modeled directly without the need for correlations.

Felver, Todd G.; Paradiso, Nicholas Joseph; Winters, William S., Jr.; Evans, Gregory Herbert; Rice, Steven F.

2010-07-01T23:59:59.000Z

383

Solidification Heat Transfer Analysis of AZ91D Cast Strip by Using a ...  

Science Conference Proceedings (OSTI)

The heat transfer coefficient between the molten magnesium ally and copper roll is important to cast magnesium strip. In the present study investigate the heat ...

384

Exploring the Limits of Boiling and Evaporative Heat Transfer Using Micro/Nano Structures.  

E-Print Network (OSTI)

??This dissertation presents a study exploring the limits of phase-change heat transfer with the aim of enhancing critical heat flux (CHF) in pool boiling and… (more)

Lu, Ming-Chang

2010-01-01T23:59:59.000Z

385

Heat Transfer Modeling of Dry Spent Nuclear Fuel Storage Facilities  

Science Conference Proceedings (OSTI)

The present work was undertaken to provide heat transfer model that accurately predicts the thermal performance of dry spent nuclear fuel storage facilities. One of the storage configurations being considered for DOE Aluminum-clad Spent Nuclear Fuel (Al-SNF), such as the Material and Testing Reactor (MTR) fuel, is in a dry storage facility. To support design studies of storage options a computational and experimental program has been conducted at the Savannah River Site (SRS). The main objective is to develop heat transfer models including natural convection effects internal to an interim dry storage canister and to geological codisposal Waste Package (WP). Calculated temperatures will be used to demonstrate engineering viability of a dry storage option in enclosed interim storage and geological repository WP and to assess the chemical and physical behaviors of the Al-SNF in the dry storage facilities. The current paper describes the modeling approaches and presents the computational results along with the experimental data.

Lee, S.Y.

1999-01-13T23:59:59.000Z

386

Rocket-borne, low gravity cryogenic heat transfer experiment  

SciTech Connect

From AIAA/NSA/ASTM/IES 7th space simulation conference; Los Angeles, Calif11nia, USA (12 Nov 1973). In order to obtain steady state data on nucleate boiling heat transfer to liquid helium in a nearly zero gravity environment a rocket-borne experiment was designed, built and successfully flown. A description of the apparatus and flight is presented along with preliminary results. (auth)

Williamson, K.D. Jr.; Edeskuty, F.J.; Taylor, J.F.

1974-04-30T23:59:59.000Z

387

Heat transfer investigations in a slurry bubble column  

SciTech Connect

Slurry bubble columns, for use in Fisher-Tropsch synthesis, have been investigated. Two bubble columns (0.108 and 0.305 m internal diameter) were set up and experiments were conducted to determine gas holdup and heat transfer coefficients. These columns were equipped with either single heat transfer probes of different diameters, or bundles of five-, seven- or thirty-seven tubes. The experiments were conducted for two- and three-phase systems; employing for gas phase: air and nitrogen, liquid phase: water and Therminol-66, and solid phase: red iron oxide (1.02, 1.70 and 2.38 {mu}m), glass beads (50.0, 90.0, 119.0 and 143.3 {mu}m), silica sand (65 {mu}), and magnetite (28.0, 35.7, 46.0, 58.0, 69.0, 90.5, 115.5, and 137.5 {mu}m). The column temperature was varied between 298--523 K, gas velocity between 0--40 cm/s, and solids concentration between 0--50 weight percent. The holdup and heat transfer data as a function of operating and system parameters were employed to assess the available correlations and semitheoretical models, and to develop new correlations. Information concerning the design and scale-up of larger units is presented. Specific research work that need to be undertaken to understand the phenomena of heat transfer and gas holdup is outlined so that efficient gas conversion and catalyst usage may be accomplished in slurry bubble columns. 130 refs., 177 figs., 54 tabs.

Saxena, S.C.; Rao, N.S.; Vadivel, R.; Shrivastav, S.; Saxena, A.C.; Patel, B.B.; Thimmapuram, P.R.; Kagzi, M.Y.; Khan, I.A.; Verma, A.K.

1991-02-01T23:59:59.000Z

388

Nonaqueous purification of mixed nitrate heat transfer media  

DOE Patents (OSTI)

A nonaqueous, in-line method for removing carbonate and hydroxide contamination from a molten mixed sodium nitrate/potassium nitrate heat transfer salt. The method comprises dissolving a stoichiometric quantity of anhydrous Ca(NO.sub.3).sub.2 in the melt whereby an insoluble CaCO.sub.3 and Ca(OH).sub.2 precipitate is formed. The precipitate can be removed by settling, filtration or floatation techniques.

Fiorucci, Louis C. (Hamden, CT); Morgan, Michael J. (Guilford, CT)

1983-12-20T23:59:59.000Z

389

Heat transfer rates for filmwise, dropwise, and superhydrophobic condensation on silicon substrates  

E-Print Network (OSTI)

Condensation, a two-phase heat transfer processes, is commonly utilized in industrial systems. Condensation heat transfer can be optimized by using surfaces in which dropwise condensation (DWC) occurs, and even further ...

Hery, Travis M

2011-01-01T23:59:59.000Z

390

Heat transfer during film condensation of potassium vapor on a horizontal plate  

E-Print Network (OSTI)

The object of the investigation is to analyze the following two features of heat transfer during condensation of potassium vapor: a. Heat transfer during film condensation of a pure saturated potassium vapor on a horizontal ...

Meyrial, Paul M.

1968-01-01T23:59:59.000Z

391

Scalable photon monte carlo algorithms and software for the solution of radiative heat transfer problems  

Science Conference Proceedings (OSTI)

Radiative heat transfer plays a central role in many combustion and engineering applications. Because of its highly nonlinear and nonlocal nature, the computational cost can be extremely high to model radiative heat transfer effects accurately. In this ...

Ivana Veljkovic; Paul E. Plassmann

2005-09-01T23:59:59.000Z

392

Experimental study of mixed convection heat transfer in vertical helically coiled tube heat exchangers  

Science Conference Proceedings (OSTI)

In this study the mixed convection heat transfer in a coil-in-shell heat exchanger for various Reynolds numbers, various tube-to-coil diameter ratios and different dimensionless coil pitch was experimentally investigated. The experiments were conducted for both laminar and turbulent flow inside coil. Effects of coil pitch and tube diameters on shell-side heat transfer coefficient of the heat exchanger were studied. Different characteristic lengths were used in various Nusselt number calculations to determine which length best fits the data and several equations were proposed. The particular difference in this study in comparison with the other similar studies was the boundary conditions for the helical coils. The results indicate that the equivalent diameter of shell is the best characteristic length. (author)

Ghorbani, N. [School of Mechanical Engineering, University of Leeds, Leeds, England (United Kingdom); Taherian, H. [Department of Engineering Technology and Industrial Distribution, Texas A and M University, College Station, TX (United States); Gorji, M. [Department of Mechanical Engineering, Babol Noushirvani University of Technology, Babol (Iran); Mirgolbabaei, H. [Department of Mechanical Engineering, Islamic Azad University, Jouybar branch, Jouybar (Iran)

2010-10-15T23:59:59.000Z

393

HEAT TRANSFER ANALYSIS FOR NUCLEAR WASTE SOLIDIFICATION CONTAINER  

SciTech Connect

The Nuclear Nonproliferation Programs Design Authority is in the design stage of the Waste Solidification Building (WSB) for the treatment and solidification of the radioactive liquid waste streams generated by the Pit Disassembly and Conversion Facility (PDCF) and Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The waste streams will be mixed with a cementitious dry mix in a 55-gallon waste container. Savannah River National Laboratory (SRNL) has been performing the testing and evaluations to support technical decisions for the WSB. Engineering Modeling & Simulation Group was requested to evaluate the thermal performance of the 55-gallon drum containing hydration heat source associated with the current baseline cement waste form. A transient axi-symmetric heat transfer model for the drum partially filled with waste form cement has been developed and heat transfer calculations performed for the baseline design configurations. For this case, 65 percent of the drum volume was assumed to be filled with the waste form, which has transient hydration heat source, as one of the baseline conditions. A series of modeling calculations has been performed using a computational heat transfer approach. The baseline modeling results show that the time to reach the maximum temperature of the 65 percent filled drum is about 32 hours when a 43 C initial cement temperature is assumed to be cooled by natural convection with 27 C external air. In addition, the results computed by the present model were compared with analytical solutions. The modeling results will be benchmarked against the prototypic test results. The verified model will be used for the evaluation of the thermal performance for the WSB drum. Detailed results and the cases considered in the calculations will be discussed here.

Lee, S.

2009-06-01T23:59:59.000Z

394

INORGANIC SALT HEAT TRANSFER FLUID - Energy Innovation Portal  

Electricity Transmission; Energy Analysis; Energy Storage; Geothermal; Hydrogen and Fuel Cell; Hydropower, Wave and Tidal; Industrial Technologies; Solar Photovoltaic;

395

Control of Fluid Flow, Heat Transfer and Inclusions in Continuous ...  

Science Conference Proceedings (OSTI)

Dynamics of Magnetically Levitated Liquid Droplets ... and Thermal Interaction of Nanoparticles in Hyperthermia Cancer Therapy and Solar Energy Systems. ... Molten Oxide Electrolysis for Lunar Oxygen Generation using in situ Resources.

396

Measurements and Predictions of the Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Exchangers  

E-Print Network (OSTI)

to the International Journal of Compact Heat Exchangers, May 2003 #12;2 Measurements and Predictions of the Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Exchangers Abstract The dominant thermal resistance for most compact heat exchangers occurs on the air side and thus a detailed understanding of air side heat

Thole, Karen A.

397

A novel approach to heat transfer enhancement using trapezoid shaped spiral strips to promote tumble and swirl in a slot shaped channel used in heat exchangers  

E-Print Network (OSTI)

Heat transfer results for a given slot shaped channel with a 3:1 aspect ratio are presented using various configurations of a trapezoid shaped spiral wound strips to enhance swirl and tumble motion in the channel. The Reynolds numbers investigated range from 10,000 to 50,000 and are based on the characteristics of the fluid at the channel inlet. The ratio of absolute temperatures between the wall and fluid are on the order of 0.8 to 0.9. A combination of thermochromic liquid crystal techniques and thermocouples were used to create a temperature vs. time map. Duhamel's superposition theorem was then used to determine the local heat transfer coefficients (h) and heat transfer enhancement factors (Nu/Nuo). In one series of testing a straight center inlet with a radiused entry was used to reduce entry effects. In a second series of test a 90 degree inlet geometry was used to enhance turbulence at the entry. Three combinations of helical strips were tested using a single, double, and pentuple spiral design. The pitch of the helix remained constant in all tests at 0.75” (18 mm) as well as the height of the strip at 0.0625” (1.6 mm), yielding a p/e (pitch/rib height) ratio of 12. The resulting flow in the channel creates a tumble motion as the main channel fluid encounters the strips and a swirl motion as the fluid is directed through the spiraling helix. Many studies involving heat transfer using swirl enhancement have been presented in literature using round passages with wire spring inserts or twisted tapes, typically used in heat exchangers. In turbine aero foils, particularly in the mid-span region, rectangular channels with various configurations of trip strips are used to enhance heat transfer. The results of the tests presented in this paper show local heat transfer enhancement (Nu/Nuo) values greater than seven and subsequent average values for the entire channel greater than three at the higher Reynolds numbers along with relatively low normalized friction factors.

Segura, D.; Acharya, S.

2012-01-01T23:59:59.000Z

398

Heat Transfer Applications for the Stimulated Reservoir Volume  

E-Print Network (OSTI)

Multistage hydraulic fracturing of horizontal wells continues to be a major technological tool in the oil and gas industry. Creation of multiple transverse fractures in shale gas has enabled production from very low permeability. The strategy entails the development of a Stimulated Reservoir Volume (SRV), defined as the volume of reservoir, which is effectively stimulated to increase the well performance. An ideal model for a shale gas SRV is a rectangle of length equal to horizontal well length and width equal to twice the half length of the created hydraulic fractures. This project focused on using the Multistage Transverse Fractured Horizontal Wells (MTFHW) for two novel applications. The first application considers using the SRV of a shale gas well, after the gas production rate drops below the economic limit, for low grade geothermal heat extraction. Cold water is pumped into the fracture network through one horizontal well drilled at the fracture tips. Heat is transferred to the water through the fracture surface. The hot water is then recovered through a second horizontal well drilled at the other end of the fracture network. The basis of this concept is to use the already created stimulated reservoir volume for heat transfer purposes. This technique was applied to the SRV of Haynesville Shale and the results were discussed in light of the economics of the project. For the second application, we considered the use of a similarly created SRV for producing hydrocarbon products from oil shale. Thermal decomposition of kerogen to oil and gas requires heating the oil shale to 700 degrees F. High quality saturated steam generated using a small scale nuclear plant was used for heating the formation to the necessary temperature. Analytical and numerical models are developed for modeling heat transfer in a single fracture unit of MTFHW. These models suggest that successful reuse of Haynesville Shale gas production wells for low grade geothermal heat extraction and the project appears feasible both technically and economically. The economics of the project is greatly aided by eliminating well drilling and completion costs. The models also demonstrate the success of using MTFHW array for heating oil shale using SMR technology.

Thoram, Srikanth

2011-08-01T23:59:59.000Z

399

Modeling of Heat and Mass Transfer in Fusion Welding  

Science Conference Proceedings (OSTI)

In fusion welding, parts are joined together by melting and subsequent solidification. Although this principle is simple, complex transport phenomena take place during fusion welding, and they determine the final weld quality and performance. The heat and mass transfer in the weld pool directly affect the size and shape of the pool, the solidification microstructure, the formation of weld defects such as porosity and humping, and the temperature distribution in the fusion zone and heat-affected zone (HAZ). Furthermore, the temperature evolution affects the kinetics and extent of various solid-state phase transformations, which in turn determine the final weld microstructure and mechanical properties. The formation of residual stresses and distortion originates from the thermal expansion and contraction during welding heating and cooling, respectively.

Zhang, Wei [ORNL

2011-01-01T23:59:59.000Z

400

Heat transfer enhancement in a tube with equilateral triangle cross sectioned coiled wire inserts  

SciTech Connect

The heat transfer and pressure drop were experimentally investigated in a coiled wire inserted tube in turbulent flow regime. The coiled wire has equilateral triangular cross section and was inserted separately from the tube wall. The experiments were carried out with three different pitch ratios (P/D = 1, 2 and 3) and two different ratio of equilateral triangle length side to tube diameter (a/D = 0.0714 and 0.0892) at a distance (s) of 1 mm from the tube wall in the range of Reynolds number from 3500 to 27,000. Uniform heat flux was applied to the external surface of the tube and air was selected as fluid. The experimental results obtained from a smooth tube were compared with those from the studies in literature for validation of experimental set-up. The use of coiled wire inserts leads to a considerable increase in heat transfer and pressure drop over the smooth tube. The Nusselt number rises with the increase of Reynolds number and wire thickness and the decrease of pitch ratio. The highest overall enhancement efficiency of 36.5% is achieved for the wire with a/D = 0.0892 and P/D = 1 at Reynolds number of 3858. Consequently, the experimental results reveal that the best operating regime of all coiled wire inserts is detected at low Reynolds number, leading to more compact heat exchanger. (author)

Gunes, Sibel; Ozceyhan, Veysel [Department of Mechanical Engineering, Faculty of Engineering, Erciyes University, Kayseri 38039 (Turkey); Buyukalaca, Orhan [Department of Energy Systems Engineering, Faculty of Engineering, Osmaniye Korkut Ata University, Osmaniye 80000 (Turkey)

2010-09-15T23:59:59.000Z

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


401

On Water Flow in Hot Fractured Rock -- A Sensitivity Study on the Impact of Fracture-Matrix Heat Transfer  

E-Print Network (OSTI)

of multiphase, multicomponent fluid mixtures in porous andmultiphase heat and mass flow in unsaturated fractured porous

Birkholzer, Jens T.; Zhang, Yingqi

2005-01-01T23:59:59.000Z

402

Heating systems for heating subsurface formations  

Science Conference Proceedings (OSTI)

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

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

2011-04-26T23:59:59.000Z

403

Advanced Binary Geothermal Power Plancts Working Fluid Property Determination and Heat Exchanger Design  

DOE Green Energy (OSTI)

The performance of binary geothermal power plants can be improved through the proper choice of a working fluid, and optimization of component designs and operating conditions. This paper reviews the investigations at the Idaho National Engineering Laboratory (INEL) which are examining binary cycle performance improvements: for moderate temperature (350 to 400 F) resources with emphasis on how the improvements may be integrated into design of binary cycles. These investigations are examining performance improvements resulting from the supercritical vaporization of mixed hydrocarbon working fluids and achieving countercurrent integral condensation with these fluids, as well as the modification of the turbine inlet state points to achieve supersaturated turbine vapor expansions. For resources where the brine outlet temperature is restricted, the use of turbine exhaust recuperators is examined. The baseline plant used to determine improvements in plant performance (characterized by the increase in the net brine effectiveness, watt-hours per pound of brine) in these studies operates at conditions similar to the 45 MW Heber binary plant. Through the selection of the optimum working fluids and operating conditions, achieving countercurrent integral condensation, and allowing supersaturated vapor expansions in the turbine, the performance of the binary cycle (the net brine effectiveness) can be improved by 25 to 30% relative to the baseline plant. The design of these supercritical Rankine-cycle (Binary) power plants for geothermal resources requires information about the potential working fluids used in the cycle. In addition, methods to design the various components, (e.g., heat exchangers, pumps, turbines) are needed. This paper limits its view of component design methods to the heat exchangers in binary power plants. The design of pumps and, turbines for these working fluids presents no new problems to the turbine manufacturer. However, additional work is proceeding at the Heat Cycle Research Facility to explore metastable expansions within turbines. This work, when completed, should allow the designer more flexibility in the state point selection in the design of these cycles which will potentially increase the system performance. The paper explores the different systems of thermodynamic and transport properties for mixtures of hydrocarbons. Methods include a computer program EXCST developed at the National Bureau of Standards in Boulder, as well as some of the thermodynamic models available in the chemical process simulation code, ASPEN, which was originally developed by the Department of Energy. The heat exchanger design methodology and computer programs of Heat Transfer Research, Inc. (HTRI) have been used because they represent data which is used throughout the industry by A & E firms as well as most heat exchanger manufacturers. For most cases, some modification of the computer results are necessary for supercritical heater design. When condensation takes place on the inside of enhanced tubes, new methods beyond HTRI's present state are necessary. The paper will discuss both of these modifications.

Bliem, C.J.; Mines, G.L.

1989-03-21T23:59:59.000Z

404

Simulation of Static Flying Attitudes with Different Heat Transfer Models for a Flying-Height Control Slider with Thermal Protrusion  

E-Print Network (OSTI)

Zhang, S. , Bogy, D.B. : A heat transfer model for thermal ?A phenomenological heat transfer model for the molecular gasWong, C.H. : A generalized heat transfer model for thin ?lm

Chen, Du; Bogy, David B.

2010-01-01T23:59:59.000Z

405

Numerical investigation of transient heat and mass transfer in a parallel-flow liquid-desiccant absorber  

E-Print Network (OSTI)

model for heat and mass transfer processes in internallyof coupled heat and mass transfer processes in liquidHeat and mass transfer in liquid des- iccant air-conditioning process

Diaz, Gerardo

2010-01-01T23:59:59.000Z

406

Direct contact heat transfer between two immiscible liquids in laminar flow between parallel plates  

DOE Green Energy (OSTI)

The search for new sources of energy has prompted studies concerned with extracting energy from low temperature geothermal reservoirs which may include investigations into direct contact heat transfer due to the caustic nature of the geothermal brine. The heat transfer between two liquids of constant properties in laminar stable flow between infinite insulated horizontal parallel plates was studied. The formulation of the general problem involves two energy equations, one for each layer, which are coupled at the interfacial boundary by conditions of temperature and energy flux compatibility. The method of solution is to use the Laplace transform which then results in the necessity of using infinite series solutions with their associated recursion relationships for the coefficients. Special solutions are developed separately for the case where the fluid properties are the same and for the case of slug-flow or constant velocity. Results are presented for the dimensionless mean temperature profile of either fluid, as they are proven to be the same, as a function of the ratios of viscosities, Peclet numbers, volumetric flow rates and the axial location.

Johnson, R.W.; Jacobs, H.R.; Boehm, R.F.

1975-12-01T23:59:59.000Z

407

Modeling the Heating of Biological Tissue based on the Hyperbolic Heat Transfer Equation  

E-Print Network (OSTI)

In modern surgery, a multitude of minimally intrusive operational techniques are used which are based on the punctual heating of target zones of human tissue via laser or radio-frequency currents. Traditionally, these processes are modeled by the bioheat equation introduced by Pennes, who considers Fourier's theory of heat conduction. We present an alternative and more realistic model established by the hyperbolic equation of heat transfer. To demonstrate some features and advantages of our proposed method, we apply the obtained results to different types of tissue heating with high energy fluxes, in particular radiofrequency heating and pulsed laser treatment of the cornea to correct refractive errors. Hopefully, the results of our approach help to refine surgical interventions in this novel field of medical treatment.

Tung, M M; Molina, J A Lopez; Rivera, M J; Berjano, E J

2008-01-01T23:59:59.000Z

408

The multiple absorption coefficient zonal method (MACZM), an efficient computational approach for the analysis of radiative heat transfer in multidimensional inhomogeneous nongray media  

E-Print Network (OSTI)

of Radiative Heat Transfer, the P-3 Approximation”, AIAAMedia”, Journal of Heat Transfer, Vol. 109, No. 3 (1987),Media”, Numerical Heat Transfer, Part B, Fundamentals, Vol.

Yuen, W W

2006-01-01T23:59:59.000Z

409

A numerical investigation on the influence of liquid properties and interfacial heat transfer during microdroplet deposition onto a glass substrate  

E-Print Network (OSTI)

This work investigates the impingement of a liquid microdroplet onto a glass substrate at different temperatures. A finite-element model is applied to simulate the transient fluid dynamics and heat transfer during the process. Results for impingement under both isothermal and non-isothermal conditions are presented for four liquids: isopropanol, water, dielectric fluid (FC-72) and eutectic tin-lead solder (63Sn-37Pb). The objective of the work is to select liquids for a combined numerical and experimental study involving a high resolution, laser-based interfacial temperature measurement to measure interfacial heat transfer during microdroplet deposition. Applications include spray cooling, micro-manufacturing and coating processes, and electronics packaging. The initial droplet diameter and impact velocity are 80 {\\mu}m and 5 m/s, respectively. For isothermal impact, our simulations with water and isopropanol show very good agreement with experiments. The magnitude and rates of spreading for all four liquids ...

Bhardwaj, Rajneesh; Attinger, Daniel

2010-01-01T23:59:59.000Z

410

Determination of a time-dependent heat transfer coefficient from non-standard boundary measurements  

Science Conference Proceedings (OSTI)

In this paper the determination of the time-dependent heat transfer coefficient in one-dimensional transient heat conduction from a non-standard boundary measurement is investigated. For this inverse nonlinear ill-posed problem the uniqueness of the ... Keywords: Boundary element method, Heat conduction, Heat transfer coefficient, Inverse problem

T. T. M. Onyango; D. B. Ingham; D. Lesnic; M. Slodi?ka

2009-01-01T23:59:59.000Z

411

Interaction and heat exchange in two-component relativistic fluid  

E-Print Network (OSTI)

A model of two-component relativistic fluid is considered, and the thermal nature of coupling between the fluid constituents is outlined. This thermal coupling is responsible for non-ideality of the fluid composite where the components are not fully independent. The interaction between particles is reflected only in the equation of state of each component, but it deals nothing with the coupling between the fluid components and does not influence the hydrodynamic motion. A general form of two-fluid decomposition is formulated for arbitrary interacting system.

Ernst Trojan; George V. Vlasov

2011-08-03T23:59:59.000Z

412

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

DOE Patents (OSTI)

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.

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

1994-01-01T23:59:59.000Z

413

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

DOE Patents (OSTI)

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.

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

1994-10-18T23:59:59.000Z

414

Effect of microfouling on heat-transfer efficiency  

DOE Green Energy (OSTI)

Field experiments, performed at Keahole Point, Hawaii and in the Gulf of Mexico, were designed to determine the relationship between decreased heat transfer efficiency and the accumulation of corrosion and/or biofouling films on heat exchanger surfaces. The sample tubes were maintained under conditions simulating those of an Ocean Thermal Energy Conversion (OTEC) system and data from the two sites have been compared. Seawater flowed through 2.54 (internal diameter) metal tubes at approximately 1.8m sec/sup -1/. Four types of tubes were used: 5052 Aluminum (A1), Grade 2 titanium (Ti), 90-10 copper-nickel (Cu-Ni) and Allegheny-Ludlum 6X stainless ssteel (SS). All surfaces were colonized by microorganisms, though colonization of the Cu-Ni surface was initially retarded. Total film weight was greatest for the Al and Cu-Ni surfaces which were characterized by corrosion as well as microbial fouling. The total organic carbon: total nitrogen ratios of the fouling films from Ti, Al, SS and Cu-Ni, 4.2, 4.0, 4.8 and 7.9 respectively, remained constant throughout the experiment. The degradation of heat transfer efficiency due to the formation of fouling layers on Ti and SS is neither linear nor a simple exponential function. A microfouling model is proposed for corrosion-resistant surfaces that is consistent with field observations.

Little, B.; Berger, L.R.

1980-01-01T23:59:59.000Z

415

Conceptual Design of Forced Convection Molten Salt Heat Transfer Testing Loop  

SciTech Connect

This report develops a proposal to design and construct a forced convection test loop. A detailed test plan will then be conducted to obtain data on heat transfer, thermodynamic, and corrosion characteristics of the molten salts and fluid-solid interaction. In particular, this report outlines an experimental research and development test plan. The most important initial requirement for heat transfer test of molten salt systems is the establishment of reference coolant materials to use in the experiments. An earlier report produced within the same project highlighted how thermophysical properties of the materials that directly impact the heat transfer behavior are strongly correlated to the composition and impurities concentration of the melt. It is therefore essential to establish laboratory techniques that can measure the melt composition, and to develop purification methods that would allow the production of large quantities of coolant with the desired purity. A companion report describes the options available to reach such objectives. In particular, that report outlines an experimental research and development test plan that would include following steps: •Molten Salts: The candidate molten salts for investigation will be selected. •Materials of Construction: Materials of construction for the test loop, heat exchangers, and fluid-solid corrosion tests in the test loop will also be selected. •Scaling Analysis: Scaling analysis to design the test loop will be performed. •Test Plan: A comprehensive test plan to include all the tests that are being planned in the short and long term time frame will be developed. •Design the Test Loop: The forced convection test loop will be designed including extensive mechanical design, instrument selection, data acquisition system, safety requirements, and related precautionary measures. •Fabricate the Test Loop. •Perform the Tests. •Uncertainty Analysis: As a part of the data collection, uncertainty analysis will be performed to develop probability of confidence in what is measured in the test loop. Overall, the testing loop will allow development of needed heat transfer related thermophysical parameters for all the salts, validate existing correlations, validate measuring instruments under harsh environment, and have extensive corrosion testing of materials of construction.

Manohar S. Sohal; Piyush Sabharwall; Pattrick Calderoni; Alan K. Wertsching; S. Brandon Grover

2010-09-01T23:59:59.000Z

416

Liquid Metal, a Heat Transport Fluid for High Temperature Solar ...  

Science Conference Proceedings (OSTI)

The need for high efficiency and direct heat conversion into hydrogen, process heat and energy storage pushes the temperature for solar concentrator systems.

417

The effect of periodic unsteady wakes on boundary layer transition and heat transfer on a curved plate.  

E-Print Network (OSTI)

??The effect of unsteady periodic wakes on heat transfer and boundary layer transition was investigated on a constant curvature heat transfer curved plate in a… (more)

Wright, Lance Cole

2012-01-01T23:59:59.000Z

418

NUMERICAL SIMULATION OF HEAT TRANSFER AND PRESSURE DROP IN PLATE HEAT EXCHANGERS USING FLUENT AS CFD TOOL.  

E-Print Network (OSTI)

??Corrugated walls are commonly used as passive devices for heat and mass transfer enhancement, being most effective in applications operated at transitional and turbulent Reynolds… (more)

EGEREGOR, DAFE

2008-01-01T23:59:59.000Z

419

Near-field radiative heat transfer for structured surfaces  

E-Print Network (OSTI)

We apply an analytical approach for determining the near-field radiative heat transfer between a metallic nanosphere and a planar semi-infinite medium with some given surface structure. This approach is based on a perturbative expansion, and evaluated to first order in the surface profile. With the help of numerical results obtained for some simple model geometries we discuss typical signatures that should be obtainable with a near-field scanning thermal microscope operated in either constant-height or constant-distance mode.

Svend-Age Biehs; Oliver Huth; Felix Rüting

2011-03-15T23:59:59.000Z

420

Grid-independent Issue in Numerical Heat Transfer  

E-Print Network (OSTI)

Grid independent is associated with the accuracy or even rationality of numerical results. This paper takes two-dimensional steady heat transfer for example to reveal the effect of grid resolution on numerical results. The law of grid dependence is obtained and a simple mathematical formula is presented. The production acquired here can be used as the guidance in choosing grid density in numerical simulation and get exact grid independent value without using infinite fine grid. Through analyzing grid independent, we can find the minimum number of grid cells that is needed to get grid-independent results. Such strategy can save computational resource while ensure a rational computational result.

Yao Wei; Wang Jian; Liao Guangxuan

2006-09-25T23:59:59.000Z

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


421

Unified Model for the Heat Transfer Processes that Occur During  

E-Print Network (OSTI)

A unified general model for the heat transfer processes that occur within a food product subjected to canning or aseptic thermal treatment, is presented. Two principles are extensively used in the model building process: system segregation and energy balancing. The model is summarized in an algorithm, whose specification is showed for different combinations of processing system type (PST) and product formulation (PF) with a single particle type. A discussion on the practical relevance of proper product identification in the case of aseptic processing, is included. Finally, an illustration is given on the results that can be obtained from the model algorithm application, in a comparative study of different PST-PF combinations.

Jose F. Pastrana; Harvey J. Gold; Kenneth R. Swanzel; Pastrana Gold; Jose F. Pastrana; Harvey J. Gold; Kenneth R. Swartzel

1992-01-01T23:59:59.000Z

422

Heat transfer augmentation along the tube wall of a louvered fin heat exchanger using practical delta winglets  

E-Print Network (OSTI)

Heat transfer augmentation along the tube wall of a louvered fin heat exchanger using practical surface of louvered fin heat exchangers. It is shown that delta winglets placed on louvered fins produce Elsevier Ltd. All rights reserved. Keywords: Compact heat exchanger; Vortex generator; Louvered fins 1

Thole, Karen A.

423

Heat and mass transfer in unsaturated porous media. Final report  

DOE Green Energy (OSTI)

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

Childs, S.W.; Malstaff, G.

1982-02-01T23:59:59.000Z

424

Local mass/heat transfer from a wall-mounted block in rectangular ...  

Science Conference Proceedings (OSTI)

Turbine blades are frequently cooled by cold fluid circulating ... cooling can lead to local blade over-heating, which ..... duced oscillations of bridge tower. J Wind ...

425

Photoreversible Micellar Solution as a Smart Drag-Reducing Fluid for Use in District Heating/Cooling Systems  

E-Print Network (OSTI)

Photoreversible Micellar Solution as a Smart Drag-Reducing Fluid for Use in District Heating solution is developed as a promising working fluid for district heating/cooling systems (DHCs). It can systems. A promising application of DR fluids is in district heating/ cooling systems (DHCs)9

Raghavan, Srinivasa

426

A combined heat transfer and quartz dissolution/deposition model for a hot dry rock geothermal reservoir  

DOE Green Energy (OSTI)

A kinetic model of silica transport has been coupled to a heat transfer model for a Hot Dry Rock (HDR) geothermal reservoir to examine the effect of silica rock-water interactions on fracture aperture and permeability. The model accounts for both the dissolution and deposition of silica. Zones of local dissolution and deposition were predicted, but their effect on aperture and permeability were fairly small for all cases studied. Initial rock temperature, reservoir size, and the ratio of rock surface area to fluid volume have the largest effect on the magnitude of silica mass transferred between the liquid and solid phases. 13 refs., 6 figs.

Robinson, B.A.; Pendergrass, J.

1989-01-01T23:59:59.000Z

427

Status of the TOUGH-FLAC simulator and recent applications related to coupled fluid flow and crustal deformations  

E-Print Network (OSTI)

multiphase fluid flow, heat transfer, and deformation in fractured porousmultiphase fluid flow, heat transfer and deformation in porousmultiphase flow of brine and gas through saline media. Transport in Porous

Rutqvist, J.

2011-01-01T23:59:59.000Z

428

Forced flow supercritical helium in a closed heat transfer loop subjected to pulsed heat loads  

Science Conference Proceedings (OSTI)

The superconducting magnets of the tokamak JT-60SA are cooled by means of forced flows of supercritical helium at 4.4 K and 0.5 MPa. The closed loops transfer heat from the magnets to the refrigerator through heat exchangers immersed into a saturated liquid helium bath. An experimental loop was designed to represent a 1/20 scaled down mock-up of JT-60SA central solenoid cooling circuits. This design for keeping the same transit times in the helium circuits

2012-01-01T23:59:59.000Z

429

CFD MODELING OF ITER CABLE-IN-CONDUIT SUPERCONDUCTORS. PART V: COMBINED MOMENTUM AND HEAT TRANSFER IN RIB ROUGHENED PIPES  

Science Conference Proceedings (OSTI)

Computational Fluid Dynamics (CFD) techniques have been proposed and applied in a series of papers to analyze cable-in-conduit conductors (CICC) for the International Thermonuclear Experimental Reactor (ITER). Previous work on the pressure drop in the central channel of ITER CICC is extended here to the problem of combined heat and momentum transfer. The CFD model, solved by the FLUENT commercial code, is first validated against 2D and 3D data from compact heat exchangers, showing good agreement. The Colburn analogy between the friction factor f and the Nusselt number Nu is not verified in the considered 2D geometries, as shown by both experiment and simulation. The validated CFD model is finally applied to the 3D analysis of central channel-like geometries relevant for ITER CICC. It is shown that the heat transfer coefficient on the central channel side stays relatively close to the smooth-pipe (Dittus-Boelter) value.

Zanino, R.; Giors, S. [Dipartimento di Energetica, Politecnico Torino, I-10129 (Italy)

2008-03-16T23:59:59.000Z

430

New correlation to predict the heat transfer coefficient in-tube cooling of supercritical CO{sub 2} in horizontal macro-tubes  

Science Conference Proceedings (OSTI)

The heat transfer coefficient during gas cooling process of supercritical CO{sub 2} without lubricating oil in horizontal macro-tubes has experimentally investigated. Investigation has done on two stainless steel circular tubes having inside-diameter of 4.55 mm and 7.75 mm and carried out for CO{sub 2} mass fluxes of 200-600 kg/m{sup 2} s, inlet fluid pressures of 7.5-10.0 MPa, and the inlet fluid temperatures of 90-100 C. The experimental results indicate that the gas cooling pressure, the inner tube diameter, the mass flux and the temperature of CO{sub 2} have significant effects on the heat transfer coefficient, especially near pseudo-critical region. The heat transfer coefficient decreases as the cooling pressure increases otherwise increases as mass flux increases. At any temperatures, smaller inner tube diameter shows higher heat transfer coefficient. In comparison between present experimental data and existing correlations from references, most of supercritical heat transfer correlations show large deviations with this present experimental data. Therefore, based on experimental data obtained in this present work, a new correlation is proposed to predict more accurate heat transfer coefficient of supercritical CO{sub 2} in horizontal macro-tubes under cooling conditions. The majority of the experimental values are within 13% of the values predicted by the new correlation. (author)

Oh, Hoo-Kyu; Son, Chang-Hyo [Department of Refrigeration and Air-Conditioning Engineering, College of Engineering, Pukyong National University, San 100, Yongdang-dong, Nam-gu, Pusan 608-739 (Korea)

2010-11-15T23:59:59.000Z

431

Heat Exchangers for Solar Water Heating Systems | Department...  

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

heat to water in a storage tank. Heat-transfer fluids, such as antifreeze, protect the solar collector from freezing in cold weather. Liquid-to-liquid heat exchangers have...

432

The effect of a magnetic field on heat transfer in a slotted channel  

SciTech Connect

The results of numerical and experimental studies of liquid metal heat transfer in slotted channels in a transverse magnetic field are presented. Test results showed an improvement in heat transfer in a straight channel at low and moderate interaction parameter, N. The Nusselt number at small N (around 120) was up to 2 times higher than in turbulent flow without a magnetic field, Peclet number being equal. This effect of heat transfer enhancement is caused by the generation and development of large scale velocity fluctuations in the near heated wall area. Qualitative and quantitative correlations between heat transfer and velocity fluctuation characteristics are presented.

Evtushenko, I.A.; Kirillov, I.R.; Sidorenkov, S.S. [D.V. Efremov Scientific Research Institute of Electrophysical Apparatus, St. Petersburg (Russian Federation); Hua, T.Q.; Reed, C.B. [Argonne National Lab., IL (United States)

1994-07-01T23:59:59.000Z

433

Dual manifold system and method for fluid transfer  

DOE Patents (OSTI)

A dual-manifold assembly is provided for the rapid, parallel transfer of liquid reagents from a microtiter plate to a solid state microelectronic device having biological sensors integrated thereon. The assembly includes aspiration and dispense manifolds connected by a plurality of conduits. In operation, the aspiration manifold is actuated such that the aspiration manifold is seated onto an array of reagent-filled wells of the microtiter plate. The wells are pressurized to force reagent through conduits toward the dispense manifold. A pressure pulse provided by a standard ink-jet printhead ejects nanoliter-to-picoliter droplets of reagent through an array of printhead orifices and onto test sites on the surface of the microelectronic device.

Doktycz, Mitchel J. (Knoxville, TN); Bryan, William Louis (Knoxville, TN); Kress, Reid (Oak Ridge, TN)

2003-05-27T23:59:59.000Z

434

Energy Basics: Solar Liquid Heating  

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

EERE: Energy Basics Solar Liquid Heating Solar liquid heating systems use a collector with a heat transfer or "working" fluid such as water, antifreeze (usually non-toxic propylene...

435

Energy Basics: Solar Air Heating  

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

EERE: Energy Basics Solar Air Heating Solar air heating systems use air as the working fluid for absorbing and transferring solar energy. Solar air collectors (devices to heat air...

436

Conjugate Effects on Steady Laminar Natural Convection Heat Transfer in Vertical Eccentric Annuli  

E-Print Network (OSTI)

Local heat flux on outer interface at channel exit i Index for bi-polar grid in the -directionConjugate Effects on Steady Laminar Natural Convection Heat Transfer in Vertical Eccentric Annuli University of Petroleum and Minerals, Dhahran, Saudi Arabia Combined conduction-free convection heat transfer

Jamal, Ahmad

437

Direct fired heat exchanger  

DOE Patents (OSTI)

A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

Reimann, Robert C. (Lafayette, NY); Root, Richard A. (Spokane, WA)

1986-01-01T23:59:59.000Z

438

Numerical solution for Stokes' first problem for a heated generalized second grade fluid with fractional derivative  

Science Conference Proceedings (OSTI)

In this paper, we consider Stokes' first problem for a heated generalized second grade fluid with fractional derivative (SFP-HGSGF). An effective implicit numerical approximation scheme (INAS) for solving the SFP-HGSGF is presented. The stability and ... Keywords: Convergence, Generalized second grade fluid, Numerical method, Stability, Stokes' first problem

Chunhong Wu

2009-10-01T23:59:59.000Z

439

Enhanced Geothermal Systems (EGS) with CO2 as Heat Transmission Fluid  

Open Energy Info (EERE)

with CO2 as Heat Transmission Fluid with CO2 as Heat Transmission Fluid Geothermal Lab Call Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Enhanced Geothermal Systems (EGS) with CO2 as Heat Transmission Fluid Project Type / Topic 1 Laboratory Call for Submission of Applications for Research, Development and Analysis of Geothermal Technologies Project Type / Topic 2 Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Project Description Previous and current attempts to develop EGS in the U.S., Japan, Europe and Australia have all employed water as a heat transmission fluid. Water has many properties that make it a favorable medium for heat extraction, but it also has serious drawbacks. The use of supercritical CO2 (scCO2) instead of water as heat extraction fluid was suggested by Donald Brown of Los Alamos National Laboratory as a "game changing" alternative that can avoid the problems of aqueous fluids, make heretofore inaccessible energy resources available for human use, and provide ancillary benefits by using and storing CO2.

440

Heating surface material’s effect on subcooled flow boiling heat transfer of R134a  

Science Conference Proceedings (OSTI)

In this study, subcooled flow boiling of R134a on copper (Cu) and stainless steel (SS) heating surfaces was experimentally investigated from both macroscopic and microscopic points of view. By utilizing a high-speed digital camera, bubble growth rate, bubble departure size, and nucleation site density, were able to be observed and analyzed from the microscopic point of view. Macroscopic characteristics of the subcooled flow boiling, such as heat transfer coefficient, were able to be measured as well. Experimental results showed that there are no obvious difference between the copper and the stainless surface with respect to bubble dynamics, such as contact angle, growth rate and departure size. On the contrary, the results clearly showed a trend that the copper surface had a better performance than the stainless steel surface in terms of heat transfer coefficient. It was also observed that wall heat fluxes on both surfaces were found highly correlated with nucleation site density, as bubble hydrodynamics are similar on these two surfaces. The difference between these two surfaces was concluded as results of different surface thermal conductivities.

Ling Zou; Barclay G. Jones

2012-11-01T23:59:59.000Z

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


441

A Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca  

Open Energy Info (EERE)

Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca Mountain, Nevada Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Site-Scale Model For Fluid And Heat Flow In The Unsaturated Zone Of Yucca Mountain, Nevada Details Activities (0) Areas (0) Regions (0) Abstract: A three-dimensional unsaturated-zone numerical model has been developed to simulate flow and distribution of moisture, gas and heat at Yucca Mountain, Nevada, a potential repository site for high-level radioactive waste. The model takes into account the simultaneous flow dynamics of liquid water, vapor, air and heat in the highly heterogeneous, fractured porous rock in the unsaturated zone (UZ). This model is intended for use in the prediction of the current and future conditions in the UZ so

442

Experimental and computational studies of loop heat pipes.  

E-Print Network (OSTI)

??Computational and experimental investigations of fluid flow and heat transfer aspects of loop heat pipes (LHPs) are presented in this thesis. The overall goal is… (more)

Atabaki, Nima.

2006-01-01T23:59:59.000Z

443

Flow and heat transfer in a curved pipe with periodically varying curvature  

SciTech Connect

A numerical analysis is carried out for the study of the flow and heat transfer for a laminar flow in a pipe with periodically varying finite (not very small) curvature. The effects of the flow rate (Re), the Prandtl number (Pr), the pipe-period ({kappa}) and the pipe-amplitude (a) on the heat transfer ratio (heat transfer of curved pipe to straight pipe) are studied. The results show that an increase in the amplitude and/or a decrease in the wavelength of a periodic wavy pipe can enhance the heat transfer rate significantly. The ratio of the heat transfer ratio to the friction ratio is greater than one which means a net benefit of heat transfer enhancement.

Yang, R.; Chang, S.F.; Wu, W.

2000-01-01T23:59:59.000Z

444

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

E-Print Network (OSTI)

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

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

2009-01-01T23:59:59.000Z

445

RELAP5 MODEL OF THE DIVERTOR PRIMARY HEAT TRANSFER SYSTEM  

SciTech Connect

This report describes the RELAP5 model that has been developed for the divertor primary heat transfer system (PHTS). The model is intended to be used to examine the transient performance of the divertor PHTS and evaluate control schemes necessary to maintain parameters within acceptable limits during transients. Some preliminary results are presented to show the maturity of the model and examine general divertor PHTS transient behavior. The model can be used as a starting point for developing transient modeling capability, including control system modeling, safety evaluations, etc., and is not intended to represent the final divertor PHTS design. Preliminary calculations using the models indicate that during normal pulsed operation, present pressurizer controls may not be sufficient to keep system pressures within their desired range. Additional divertor PHTS and control system design efforts may be required to ensure system pressure fluctuation during normal operation remains within specified limits.

Popov, Emilian L [ORNL; Yoder Jr, Graydon L [ORNL; Kim, Seokho H [ORNL

2010-08-01T23:59:59.000Z

446

Pressure drop and heat transfer characteristics of boiling water in sub-hundred micron channel  

SciTech Connect

The current work focuses on the pressure drop, heat transfer and stability in two phase flow in microchannels with hydraulic diameter of less than one hundred microns. Experiments were conducted in smooth microchannels of hydraulic diameter of 45, 65 {mu}m, and a rough microchannel of hydraulic diameter of 70 {mu}m, with deionised water as the working fluid. The local saturation pressure and temperature vary substantially over the length of the channel. In order to correctly predict the local saturation temperature and subsequently the heat transfer characteristics, numerical techniques have been used in conjunction with the conventional two phase pressure drop models. The Lockhart-Martinelli (liquid-laminar, vapour-laminar) model is found to predict the two phase pressure drop data within 20%. The instability in two phase flow is quantified; it is found that microchannels of smaller hydraulic diameter have lesser instabilities as compared to their larger counterparts. The experiments also suggest that surface characteristics strongly affect flow stability in the two phase flow regime. The effect of hydraulic diameter and surface characteristics on the flow characteristics and stability in two phase flow is seldom reported, and is of considerable practical relevance. (author)

Bhide, R.R.; Singh, S.G.; Sridharan, Arunkumar; Duttagupta, S.P.; Agrawal, Amit [Department of Mechanical Engineering, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India)

2009-09-15T23:59:59.000Z

447

A method of correlating heat transfer data for surface boiling of liquids  

E-Print Network (OSTI)

A method based an a logical uxplanation of the meani of beat transfer associated with the boiling process is presented for correlating heat transfer data for nucleate boiling of liquids for the case of pool boiling. Tbe ...

Rohsenow, Warren M.

1951-01-01T23:59:59.000Z

448

FUNDAMENTAL INVESTIGATION OF BOILING HEAT TRANSFER AND TWO-PHASE FLOW  

SciTech Connect

Significantly improved theories of two-phase heat transfer and prediction of departure from nucleate boiling have recently been developed which for the first time are not based on empirical relationships. These theories should be critically analyzed in relation to naval reactor work and tested with all existing data from both classified and unclassified sources. Conflicting analyses of two-phase fluid fiow regimes confuse this area, and essentially no data or theories are avsilable for twophase fiow with superimposed boiling. Theories and understanding of two-phase flow with boiling should be developed, starting from proven theories without boiling, and tested against all existing data or new data as necessary. A substantial start hss been made in analysis of the case of upward annular two-phase flow in vertical channels, based upon modern knowledge of boundary layer and vapor condensation principles. (auth)

Grohse, E.W.; Mueller, G.O.; Findlay, J.A.

1958-10-17T23:59:59.000Z

449

Application of mechanistic models for flow distribution and heat transfer in finned tube bundles.  

E-Print Network (OSTI)

?? The focus of this thesis was heat transfer and pressure drop in staggered tube bundles with solid and serrated fins. The first part of… (more)

Eikill, Astrid Oygarden

2013-01-01T23:59:59.000Z

450

Heat and mass transfer in deep fat frying of breaded chicken nuggets.  

E-Print Network (OSTI)

??This study presents techniques that can be applied to optimize the quality of coated fried chicken nuggets. Heat and mass transfer during deep fat frying… (more)

Wang, Yunfeng, 1970-

2005-01-01T23:59:59.000Z

451

Heat transfer characteristics of a two-phase, air-water direct contact evaporator.  

E-Print Network (OSTI)

??The purpose of the research was to carry out an experimental and theoretical investigation of the heat transfer on a direct contact column for desalination… (more)

Zanette, Luca

2013-01-01T23:59:59.000Z

452

Effect of TiO2 on the Conduction Heat Transfer of Mold Flux  

Science Conference Proceedings (OSTI)

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

453

Flow fields and heat transfer of liquid falling film on horizontal cylinders.  

E-Print Network (OSTI)

??A liquid film flowing over horizontal cylinders is of great importance as a high rate of heat transfer exists between the falling liquid film and… (more)

Jafar, Farial A

2011-01-01T23:59:59.000Z

454

Application Of A Spherical-Radial Heat Transfer Model To Calculate...  

Open Energy Info (EERE)

Application Of A Spherical-Radial Heat Transfer Model To Calculate Geothermal Gradients From Measurements In Deep Boreholes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal...

455

Impingement cooling and heat transfer measurement using transient liquid crystal technique.  

E-Print Network (OSTI)

??A heat transfer study on jet impingement cooling is presented. The study focuses on the effect of impingement jet flow rate, jet angle, and flow… (more)

Huang, Yizhe

2012-01-01T23:59:59.000Z

456

Modeling of Heat Transfer during Cooling of a Hot Steel Plate  

Science Conference Proceedings (OSTI)

Thus, it is crucial to develop accurate heat transfer models in order to predict the temperature history during cooling of steel plates. The present study describes a  ...

457

Heat transfer modeling at an interface between a porous medium and a free region.  

E-Print Network (OSTI)

??This work deals with the study of heat transfer between a porous medium and a free medium, using multi scale approaches. First, we derive the… (more)

D'hueppe, Aliénor

2011-01-01T23:59:59.000Z

458

Dynamic wetting and heat transfer behaviour of aluminium droplets impinging and solidifying on copper substrates.  

E-Print Network (OSTI)

??The present work describes an experimental set-up built to simulate dynamic wetting and heat transfer occurring in many rapid solidification processes. Tests were performed with… (more)

Leboeuf, Sébastien

2004-01-01T23:59:59.000Z

459

Heat transfer to and from a reversible thermosiphon placed in porous media.  

E-Print Network (OSTI)

??The primary focus of this work is an assessment of heat transfer to and from a reversible thermosiphon imbedded in porous media. The interest in… (more)

Kekelia, Bidzina

2012-01-01T23:59:59.000Z

460

The Development of a Non-Equilibrium Dispersed Flow Film Boiling Heat Transfer Modeling Package.  

E-Print Network (OSTI)

??The dispersed flow film boiling (DFFB) heat transfer regime is important to several applications including cryogenics, rocket engines, steam generators, and in the safety analysis… (more)

Meholic, Michael

2011-01-01T23:59:59.000Z

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