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


1

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

2

Cryogenic Fluid Flow Heat Transfer in a Porous Heat Exchanger  

Science Journals Connector (OSTI)

The recent utilization of porous heat exchangers in various key industries has aroused considerable interest in the heat transfer and fluid dynamics processes in channel flows involving suction...1], suction with...

L. L. Vasiliev; G. I. Bobrova; S. K. Vinokurov…

1978-01-01T23:59:59.000Z

3

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...

Singh, K. P.

1979-01-01T23:59:59.000Z

4

Hydrodynamics, heat transfer and flow boiling instabilities in microchannels   

E-Print Network [OSTI]

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

Barber, Jacqueline Claire

2010-01-01T23:59:59.000Z

5

16 Heat Transfer and Air Flow in a Domestic Refrigerator  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

6

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

E-Print Network [OSTI]

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

Aussillous, Pascale

7

Radiative heat transfer in a flow of rheologically complex fluid  

Science Journals Connector (OSTI)

The problem of complex radiative and convective heat transfer in steady-state generalized Couette flow of a nonlinear viscoplastic fluid is examined.

V. F. Volchenok; Z. P. Shul'man

1980-09-01T23:59:59.000Z

8

Heat transfer research on supercritical water flow upward in tube  

SciTech Connect (OSTI)

The experimental research of heat transfer on supercritical water has been carried out on the supercritical water multipurpose test loop with a 7.6 mm upright tube. The experimental data of heat transfer is obtained. The experimental results of thermal-hydraulic parameters on flow and heat transfer of supercritical water show that: Heat transfer enhancement occurs when the fluid temperature reaches pseudo-critical point with low mass flow velocity, and peters out when the mass flow velocity increases. The heat transfer coefficient and Nusselt number decrease with the heat flux or system pressure increases, and increase with the increasing of mass flow velocity. The wall temperature increases when the mass flow velocity decreases or the system pressure increases. (authors)

Li, H. B.; Yang, J. [China Nuclear Power Technology Research Inst., Shenzhen, Guangdong (China); Gu, H. Y.; Zhao, M. [Shanghai Jiao Tong Univ., Shanghai (China); Lu, D. H.; Zhang, J. M.; Wang, F.; Zhang, Y. [China Nuclear Power Technology Research Inst., Shenzhen, Guangdong (China)

2012-07-01T23:59:59.000Z

9

FLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS  

E-Print Network [OSTI]

= heat, f = LO-mode, g = LO, h = LA-mode, i = negligible, j = remote heat sink 7/ 70 #12;Heat conductionFLUID MECHANICS AND HEAT TRANSFER OF ELECTRON FLOW IN SEMICONDUCTORS Mihir Sen Department · Shallow water analogy · Vorticity dynamics · Linear stability analysis · Numerical simulations of heat

Sen, Mihir

10

Heat transfer in channel flow of a micropolar fluid  

Science Journals Connector (OSTI)

The study of heat transfer in channel flow has been done by previous authors for Newtonian and elastico-viscous fluids. It is the aim of the present ... the temperature profile for flow of a micropolar fluid in a...

Renuka Rajagopalan; K. S. Bhatnagar

1969-10-01T23:59:59.000Z

11

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 geometry the flow field influence on the local heat transfer distribution on an evenly cooled scraped heat loss heat loss to the surroundings stst stainless steel plate lc thermo-chromic liquid crystal

Boyer, Edmond

12

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

13

MERLOT: a model for flow and heat transfer through porous media for high heat flux applications  

E-Print Network [OSTI]

MERLOT: a model for flow and heat transfer through porous media for high heat flux applications A Abstract Fusion power plant studies have found helium to be an attractive coolant based on its safety tend to provide modest heat transfer performance due to their inherently low heat capacity and heat

Raffray, A. René

14

Heat Transfer at Low Temperatures between Tube Walls and Gases in Turbulent Flow  

Science Journals Connector (OSTI)

...September 1947 research-article Heat Transfer at Low Temperatures between Tube...counter-flow system to study heat transfer between tube walls and gases at...Determinations on friction accompanying heat transfer with gases in turbulent flow at...

1947-01-01T23:59:59.000Z

15

Numerical Evaluation of Flow and Heat Transfer in Plate-Pin Fin Heat Sinks with Various Pin Cross-Sections  

E-Print Network [OSTI]

Liu, Research on the Heat Transfer and Flow Performance of aCompound Heat Sink, Numer. Heat Transfer A, vol. 55, no. 5,Hand- book of Numerical Heat Transfer, 2nd ed. , chap. 6,

Zhou, Feng; Catton, Ivan

2011-01-01T23:59:59.000Z

16

Experimental study of fluid flow and heat transfer in tortuous microchannels.  

E-Print Network [OSTI]

??Tortuous microchannels have attracted increasing interest due to great potential to enhance fluid mixing and heat transfer. While the fluid flow and heat transfer in… (more)

Dai, Zhenhui

2014-01-01T23:59:59.000Z

17

Heat transfer during laminar fluid flow in a pipe with radiative heat removal  

Science Journals Connector (OSTI)

The heat-transfer problem is analyzed for laminar fluid flow in the initial section of a ... pipe having a parabolic entry velocity distribution and heat removal by radiation from the surface of...

Ya. S. Kadaner; Yu. P. Rassadkin; É. L. Spektor

1971-01-01T23:59:59.000Z

18

A visualization comparison of convective flow boiling heat transfer augmentation devices  

E-Print Network [OSTI]

The qualitative effects of inset-table heat transfer phics. augmentation devices on vertical in-tube convective flow boiling flow regimes, transition mechanisms, and heat transfer are presented in this study. Three twisted tapes with twist ratios...

Lundy, Brian Franklin

2012-06-07T23:59:59.000Z

19

Heat transfer in the flow of a viscoelastic fluid over a stretching sheet  

Science Journals Connector (OSTI)

The problem of heat transfer in the viscoelastic fluid flow over a stretching sheet is examined. ... such as the skin-friction coefficient and the heat transfer coefficient, are determined. It is found that the heat

P. Sam Lawrence; Dr. B. Nageswara Rao

1992-01-01T23:59:59.000Z

20

The developing heat transfer and fluid flow in micro-channel heat sink with viscous heating effect  

Science Journals Connector (OSTI)

The numerical modeling of the conjugate heat transfer and fluid flow through the micro-heat sink was presented in the paper, considering the viscous dissipation effect. Three different fluids with temperature dep...

Dorin Lelea; Adrian Eugen Cioabla

2011-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

NUMERICAL SIMULATIONS OF HEAT TRANSFER AND FLUID FLOW PROBLEMS USING AN  

E-Print Network [OSTI]

NUMERICAL SIMULATIONS OF HEAT TRANSFER AND FLUID FLOW PROBLEMS USING AN IMMERSED-BOUNDARY FINITE of the immersed boundary technique for simulating fluid flow and heat transfer problems over or inside complex. Several phenomenologically different fluid flow and heat transfer problems are simulated using

Pacheco, Jose Rafael

22

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

E-Print Network [OSTI]

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

Le Roy, Robert J.

23

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

E-Print Network [OSTI]

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

Abdou, Mohamed

24

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

E-Print Network [OSTI]

1 FLIHY EXPERIMENTAL FACILITIES FOR STUDYING OPEN CHANNEL TURBULENT FLOWS AND HEAT TRANSFER B was constructed at UCLA to study open channel turbulent flow and heat transfer of low-thermal and low supercritical flow regimes (Fr>1), in which the surface waves are amplified and heat transfer is enhanced due

California at Los Angeles, University of

25

Numerical simulations of heat transfer in plane channel flow Najla EL GHARBI 1, 3, a  

E-Print Network [OSTI]

Numerical simulations of heat transfer in plane channel flow Najla EL GHARBI 1, 3, a , Rafik ABSI 2 abenzaoui@gmail.com Keywords: turbulent flows, heat transfer, forced convection, low Reynolds number model data for Re = 150. Introduction Turbulent flow with heat transfer mechanism is of great importance from

Paris-Sud XI, Université de

26

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

E-Print Network [OSTI]

for Simulating Fluid Flow and Heat Transfer in Unsaturatedcomplex multiphase fluid flow and heat-transfer processes.of the coupled fluid-flow and heat-transfer processes has

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

2005-01-01T23:59:59.000Z

27

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

28

Flow and heat transfer around a linear array of spheres  

SciTech Connect (OSTI)

Laminar fluid flow and forced convection heat transfer over equally space linear arrays of spheres are analyzed using the finite element package FIDAP. For the arrays, sphere spacings of 1.5, 2, and 3 diameters are examined at Reynolds numbers of 40, 80, and 120 and Prandtl numbers ranging from 0.73 to 7.3. Average Nusselt numbers and drag coefficient data for a linear array of eight spheres (as an approximation to the developing region) and a single sphere with periodic boundary conditions (as an approximation to fully developed flow) are presented and correlated.

Lloyd, B. (Marathon Oil Co., Shreveport, LA (United States)); Boehn, R. (Univ. of Nevada, Las Vegas, NV (United States). Mechanical Engineering Dept.)

1994-08-01T23:59:59.000Z

29

Review of fluid flow and convective heat transfer within rotating disk cavities  

E-Print Network [OSTI]

Review of fluid flow and convective heat transfer within rotating disk cavities with impinging jet * Corresponding author : souad.harmand@univ-valenciennes.fr Abstract Fluid flow and convective heat transfer, are treated in details in this review. The review focuses on convective heat transfer in predominantly outward

Boyer, Edmond

30

Review of fluid flow and convective heat transfer within rotating disk cavities  

E-Print Network [OSTI]

1 Review of fluid flow and convective heat transfer within rotating disk cavities with impinging axial direction #12;5 Introduction Fluid flow and convective heat transfer in rotor-stator configuration heat transfer in rotor-stator configurations, which are of great importance in different engineering

Paris-Sud XI, Université de

31

Numerical modeling of fluid flow and heat transfer in a narrow Taylor-Couette-Poiseuille system  

E-Print Network [OSTI]

Numerical modeling of fluid flow and heat transfer in a narrow Taylor-Couette-Poiseuille system S [1, 2] widely validated in various rotor-stator cavities with throughflow [3­5] and heat transfer [6: RANS modeling, Reynolds Stress Model, Taylor-Couette-Poiseuille flow, turbulence, heat transfer. hal

Paris-Sud XI, Université de

32

The effects of topology upon fluid-flow and heat-transfer within cellular copper structures  

E-Print Network [OSTI]

The effects of topology upon fluid-flow and heat-transfer within cellular copper structures J. Tian February 2004 Available online 20 March 2004 Abstract The fluid-flow and heat-transfer features of cellular and packed beds, but also a function of orientation (open area ratio). The overall heat transfer depends

Wadley, Haydn

33

The effects of topology upon fluid-flow and heat-transfer within cellular copper structures  

E-Print Network [OSTI]

1 The effects of topology upon fluid-flow and heat-transfer within cellular copper structures J The fluid-flow and heat-transfer features of copper cellular metal structures made by the transient liquid media. The experimental results for pressure drop and heat transfer were expressed on the basis

Wadley, Haydn

34

Finite element solutions of heat transfer in molten polymer flow in tubes with viscous dissipation  

E-Print Network [OSTI]

Finite element solutions of heat transfer in molten polymer flow in tubes with viscous dissipation the results of finite element analysis of a heat transfer problem of flowing polymer melts in a tube­Nusselt problem 1. Introduction Heat transfer to incompressible viscous non-Newto- nian fluids is a problem

Wei, Dongming

35

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

E-Print Network [OSTI]

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

Kostic, Milivoje M.

36

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

E-Print Network [OSTI]

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

Kandlikar, Satish

37

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

E-Print Network [OSTI]

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

Boyer, Edmond

38

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

E-Print Network [OSTI]

development of fluid flow and heat transfer models at otherTOUGH2 code [22]. Fluid flow and heat-transfer processes inand heat transfer through fractured rock is based on the DKM method. This approach considers global fluid and

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

2006-01-01T23:59:59.000Z

39

Lattice Boltzmann method for rarefied channel flows with heat transfer  

Science Journals Connector (OSTI)

Abstract A thermal lattice Boltzmann method (TLBM) is presented for the analysis of fluid flow and heat transfer in two-dimensional channels with non-continuum effects. The relaxation times ( ? f , ? g ) are linked to the Knudsen number which accounts for the rarefaction that can be present at micro geometries or at low density conditions. The TLBM used here employs inlet/outlet boundary conditions to generate a forced convection problem where the calculation of equilibrium distributions at the wall surfaces are modified to incorporate the velocity slip and temperature jump conditions. Numerical simulations are obtained for thermal micro-Couette and thermal micro-Poiseuille channel flows and the effect of the Knudsen number on the velocity and temperature profile is investigated.

Seckin Gokaltun; George S. Dulikravich

2014-01-01T23:59:59.000Z

40

EXPERIMENTAL INVESTIGATION OF TURBULENT HEAT TRANSFER OF HIGH PRANDTL NUMBER FLUID FLOW UNDER STRONG MAGNETIC FIELD  

E-Print Network [OSTI]

EXPERIMENTAL INVESTIGATION OF TURBULENT HEAT TRANSFER OF HIGH PRANDTL NUMBER FLUID FLOW UNDER to the heat transfer characteristic: Flibe is a high Prandtl number fluid. For high Prandtl number fluid, there is a severe limitation of temperature window due to its high melting point. The turbulent heat transfer is

Abdou, Mohamed

Note: This page contains sample records for the topic "flow heat transfer" 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

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

E-Print Network [OSTI]

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

Boyer, Edmond

42

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

E-Print Network [OSTI]

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

Kandlikar, Satish

43

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

44

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

45

Heat transfer in the nonisothermal flow of an anomalously viscous fluid in a helical duct  

Science Journals Connector (OSTI)

The problem of heat transfer in the initial section of a helical ... with a steady flow of an anomalously viscous fluid is solved numerically.

A. I. Mumladze; Yu. G. Nazmeev; O. V. Maminov

1982-08-01T23:59:59.000Z

46

Coupled flow and heat transfer in viscoelastic fluid with Cattaneo–Christov heat flux model  

Science Journals Connector (OSTI)

Abstract This letter presents a research for coupled flow and heat transfer of an upper-convected Maxwell fluid above a stretching plate with velocity slip boundary. Unlike most classical works, the new heat flux model, which is recently proposed by Christov, is employed. Analytical solutions are obtained by using the homotopy analysis method (HAM). The effects of elasticity number, slip coefficient, the relaxation time of the heat flux and the Prandtl number on velocity and temperature fields are analyzed. A comparison of Fourier’s Law and the Cattaneo–Christov heat flux model is also presented.

Shihao Han; Liancun Zheng; Chunrui Li; Xinxin Zhang

2014-01-01T23:59:59.000Z

47

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

E-Print Network [OSTI]

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

Maruyama, Shigeo

48

A general heat transfer correlation for non-boiling gasliquid flow with different flow patterns  

E-Print Network [OSTI]

, such as oil wells and pipelines, solar collectors, chemical reactors, and nuclear reactors, and its in horizontal pipes Jae-yong Kim, Afshin J. Ghajar * School of Mechanical and Aerospace Engineering, Oklahoma patterns in horizontal pipes is proposed. In order to overcome the effect of flow pattern on heat transfer

Ghajar, Afshin J.

49

Melting heat transfer effects on stagnation point flow of micropolar fluid saturated in porous medium with internal heat generation (absorption)  

Science Journals Connector (OSTI)

The effect of melting heat transfer on the two dimensional boundary layer flow of a micropolar fluid near a stagnation point embedded in a porous medium in the presence of internal heat generation/absorption is i...

M. A. A. Mahmoud; S. E. Waheed

2014-08-01T23:59:59.000Z

50

3D Numerical heat transfer and fluid flow analysis in plate-fin and tube heat exchangers with electrohydrodynamic enhancement  

Science Journals Connector (OSTI)

Three-dimensional laminar fluid flow and heat transfer over a four-row plate-fin and tube heat exchanger with electrohydrodynamic (EHD) wire electrodes...V E...=0–16 kV) are investigated in detail...

Chia-Wen Lin; Jiin-Yuh Jang

2005-05-01T23:59:59.000Z

51

Taylor bubble-train flows and heat transfer in the context of Pulsating Balkrishna Mehta, Sameer Khandekar  

E-Print Network [OSTI]

Taylor bubble-train flows and heat transfer in the context of Pulsating Heat Pipes Balkrishna Mehta Nusselt number Heat transfer enhancement a b s t r a c t Understanding the performance of Pulsating Heat Pipes (PHPs) requires spatio-temporally coupled, flow and heat transfer information during the self

Khandekar, Sameer

52

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

E-Print Network [OSTI]

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

Soti, Atul Kumar; Sheridan, John

2015-01-01T23:59:59.000Z

53

Flow and heat transfer in porous micro heat sink for thermal management of high power LEDs  

Science Journals Connector (OSTI)

A novel porous micro heat sink system is presented for thermal management of high power LEDs, which has high heat transport capability. The operational principle and heat transfer characteristics of porous micro heat sink are analyzed. Numerical model ... Keywords: Heat dissipation, High heat flux, High power LEDs, Porous media, Porous micro heat sink

Z. M. Wan; J. Liu; K. L. Su; X. H. Hu; S. S. M

2011-05-01T23:59:59.000Z

54

A Refined Model of Stationary Heat Transfer in Composite Bodies Reinforced with Pipes Containing a Heat-Transfer Fluid Moving in Laminar Flow Conditions  

Science Journals Connector (OSTI)

Equations describing the stationary heat conduction of composite bodies spatially reinforced with ... of smooth pipes, through which an incompressible heat-transfer fluid is pumped in laminar flow conditions, are...

A. P. Yankovskii

2014-03-01T23:59:59.000Z

55

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

E-Print Network [OSTI]

. . Heat transfer and Flutd flow results ? Counter flow . 32 64 CONCLUSIONS . 101 REFERENCES . 104 APPENDIX A. APPENDIX B APPENDIX C LIST OF FIGURES FIGURE 1 Detailed Schematic of the Test Section with the Flow Loop for 81. 27cm Inner pipe... with Parallel Flow. . 2 Schematic Diagram showing the arrangement of the mner pipes with different diameters with the copper segments. 3 Schematic of the test section showmg the two different flow arrangements (Parallel Flow and Counter Flow) . Page 12 14...

Mhetras, Shantanu Prakash

2012-06-07T23:59:59.000Z

56

ECI International Conference on Heat Transfer and Fluid Flow in Microscale Whistler, 21-26 September 2008  

E-Print Network [OSTI]

ECI International Conference on Heat Transfer and Fluid Flow in Microscale Whistler, 21] studied convective heat transfer of slug flows in a macro-sized tube by using viscoelastic fluids-26 September 2008 NUMERICAL STUDY ON CONVECTIVE HEAT TRANSFER OF GAS-LIQUID SLUG FLOW IN A MICRO TUBE Qunwu He

Kasagi, Nobuhide

57

PHYSICAL REVIEW E 84, 048302 (2011) Reply to "Comment on `Heat transfer and fluid flow in microchannels and nanochannels  

E-Print Network [OSTI]

PHYSICAL REVIEW E 84, 048302 (2011) Reply to "Comment on `Heat transfer and fluid flow) model for high-Knudsen-number (Kn) flow and heat transfer, in the range of Kn 1. We present various studies employing the LBGK model for high-Kn flow and heat transfer simulations. It is concluded that

Luo, Li-Shi

58

Experimental Study of Heat Transfer and Flow Characteristics for a New Type of Air Heater  

E-Print Network [OSTI]

. It is found that the integrated characteristics of heat transfer and flow friction increase with the hole's diameter at the same hole density (which is equal to the ratio of the hole's total area to the baffle's area), and the heat transfer rate increases...

Zheng, H.; Fan, X.; Li, A.

2006-01-01T23:59:59.000Z

59

BUBBLE CHARACTERISTICS AND CONVECTIVE EFFECTS IN THE FLOW BOILING HEAT TRANSFER OF BINARY MIXTURES  

E-Print Network [OSTI]

BUBBLE CHARACTERISTICS AND CONVECTIVE EFFECTS IN THE FLOW BOILING HEAT TRANSFER OF BINARY MIXTURES on the bubble growth and associated heat transfer phenomena. The present work focuses on obtaining the bubble. The bubble growth is observed using a high speed camera (1000 fps) under a magnification of 290X. The bubble

Kandlikar, Satish

60

Heat transfer and pressure drop for air flow through enhanced passages  

SciTech Connect (OSTI)

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 "flow heat transfer" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

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

SciTech Connect (OSTI)

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

62

Numerical investigation of flow structure and mixed convection heat transfer of impinging radial and axial jets  

SciTech Connect (OSTI)

Mixed convection flow fields and heat transfer of partially enclosed axial and radial laminar jets impinging on a heated flat plate have been investigated from the numerical solution of incompressible unsteady Navier-Stokes and energy equations with a Boussinesq approximation. For mixed convection flow at Re = 200, steady flow has not been observed for either the radial or the axial jet. For the smallest Grashof number (Gr = 10,000), periodic solutions have been obtained. With Gr = 40,000 nonsteady nonperiodic (chaotic) flow appears. Free convection may increase that heat transfer by more than 200%.

Potthast, F.; Laschefski, H.; Mitra, N.K. (Ruhr-Univ. Bochum (Germany). Inst. fuer Thermo- und Fluiddynamik); Biswas, G. (Indian Inst. of Tech., Kanpur (India). Dept. of Mechanical Engineering)

1994-08-01T23:59:59.000Z

63

NUMERICAL STUDY OF FLUID FLOW AND HEAT TRANSFER OVER A SERIES OF IN-LINE NONCIRCULAR  

E-Print Network [OSTI]

NUMERICAL STUDY OF FLUID FLOW AND HEAT TRANSFER OVER A SERIES OF IN-LINE NONCIRCULAR TUBES CONFINED, Texas A&M University, College Station, Texas, USA Two-dimensional steady developing fluid flow and heat-volume technique. Grid independence study was carried out by running the developed code for several different grid

Bahaidarah, Haitham M.

64

Local heat and mass transfer for gas-solid two phase flow in CFB  

Science Journals Connector (OSTI)

An experimental investigation on the flow characteristics and the local heat and mass transfer between coarse wet particles and hot gas in the circulating fluidized bed (CFB) has been performed. A two-thermocoupl...

Feng Lu; Ming-Heng Shi

1994-09-01T23:59:59.000Z

65

Heat transfer due to stagnation point flow of a non-Newtonian fluid  

Science Journals Connector (OSTI)

Heat transfer analysis for steady, laminar flow of an incompressible, homogeneous, non-Newtonian fluid of second grade at a stagnation point...K, of the fluid. The energy equation is discretized using central ......

V. K. Garg

1994-01-01T23:59:59.000Z

66

Heat-transfer mechanism in turbulent flow of fluid at supercritical pressures  

Science Journals Connector (OSTI)

A hypothetical physical model of the heat-transfer process accompanying a forced flow of liquid at supercritical pressures is proposed. This model accounts for the anomalous improvements and deteriorations in ...

Sh. G. Kaplan

1971-09-01T23:59:59.000Z

67

Second-order fluid flow past a stretching sheet with heat transfer  

Science Journals Connector (OSTI)

The heat transfer in the flow of a second-order fluid, obeying Coleman and Noll's constitutive equation...KC/v. The thermal boundary layer thickness decreases and the Nusselt numberNu x increases ...

N. M. Bujurke; S. N. Biradar; P. S. Hiremath

1987-07-01T23:59:59.000Z

68

Unsteady hydromagnetic free-convection flow with radiative heat transfer in a rotating fluid  

Science Journals Connector (OSTI)

We consider the buoyancy-induced flow of an electrically-conducting fluid with radiative heat transfer past a vertical flat plate of infinite ... vary with temperature, that is a compressible fluid. If the temper...

A. R. Bestman; S. K. Adjepong

69

Heat transfer in a radiating fluid with slug flow in a parallel-plate channel  

Science Journals Connector (OSTI)

As a step towards a better understanding of combined conduction, convection, and radiation, fully developed heat transfer in slug flow in a flat duct ... , nonblack, isothermal surfaces. The gray radiating fluid ...

R. Viskanta

1964-01-01T23:59:59.000Z

70

Heat transfer in an MHD channel flow with boundary conditions of the third kind  

Science Journals Connector (OSTI)

The heat transfer equation for a two-dimensional magnetohydrodynamic channel flow has been solved using boundary conditions of the third kind considering a discontinuity in the “ambient” temperature. The bound...

Sergio Cuevas; Eduardo Ramos

1991-01-01T23:59:59.000Z

71

Numerical study of flow and heat transfer in 3D serpentine channels using colocated grids  

E-Print Network [OSTI]

and average Nusselt number. The numerical code developed was validated by solving for fully developed flow and heat transfer in a square straight channel. Grid-independent solution was established for a reference case of serpentine channel with the highest...

Chintada, Sailesh Raju

1998-01-01T23:59:59.000Z

72

Heat transfer to a fluid flowing in an annulus  

E-Print Network [OSTI]

. ii I ~ DIMENSIONS AND SYMBOLS o ~ ~ ~ . ~ ~ ~ ~ I II e INTRODUCTION AND THEORY ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 3 IXI e APPARATUS AND PROCEDURES ~ ~ e ~ ~ ~ ~ ~ ~ ~ ~ 7 XV o RESULTS ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ e ~ ~ ~ ~ 17 V, DXSCUSSION OF RESULTS... of times 0 Prandtl nnnber~ e~& dimensionless initial temperature oi' surfaoe and fluids% D equivalent diameter& Di g~ L Q - volume flow rate~ L3/T V~ mass velooity, FT/L3 6 mass floe rate~ FT/L IMTRODUCTIOR AND THEORY This thesis comprises heat tz...

Logan, Earl

2012-06-07T23:59:59.000Z

73

Finite element analysis of conjugate heat transfer in axisymmetric pipe flows  

E-Print Network [OSTI]

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

Fithen, Robert Miller

2012-06-07T23:59:59.000Z

74

Experimental Study on Heat Transfer of Single-Phase Flow and Boiling Two-Phase Flow in Vertical Narrow Annuli  

SciTech Connect (OSTI)

Water single-phase and nucleate boiling heat transfer were experimentally investigated in vertical annuli with narrow gaps. The experimental data about water single-phase flow and boiling two-phase flow heat transfer in narrow annular channel were accumulated by two test sections with the narrow gaps of 1.0 mm and 1.5 mm. Empirical correlations to predict the heat transfer of the single-phase flow and boiling two-phase flow in the narrow annular channel were obtained, which were arranged in the forms of the Dittus-Boelter for heat transfer coefficients in a single-phase flow and the Jens-Lottes formula for a boiling two-phase flow in normal tubes, respectively. The mechanism of the difference between the normal channel and narrow annular channel were also explored. From experimental results, it was found that the turbulent heat transfer coefficients in narrow gaps are nearly the same to the normal channel in the experimental range, and the transition Reynolds number from a laminar flow to a turbulent flow in narrow annuli was much lower than that in normal channel, whereas the boiling heat transfer in narrow annular gap was greatly enhanced compared with the normal channel. (authors)

Suizheng Qiu; Guanghui Su; Dounan Jia [Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, Shaanxi, 710049 (China); Minoru Takahashi [Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152 (Japan)

2002-07-01T23:59:59.000Z

75

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

76

Analysis of cross-flow mixed convection with applications to building heat transfer  

SciTech Connect (OSTI)

A numerical simulation model has been developed for partial enclosure with restricted inlet and outlet simulating the building fluid flow and heat transfer scenario. Computed results are presented for a number of geometric configurations over a wide range of Reynolds and Rayleigh numbers and validated with available experimental data. The physical processes were modeled by solving equations for the conservation of mass, momentum, and energy with appropriate boundary conditions. The properties of the fluid were assumed to remain approximately constant over the range of operation and the buoyancy was incorporated using the Boussinesq approximation. The k-{var_epsilon} model was used for the simulation of turbulence. The computed results included the local velocity and temperature and the variation of local heat transfer coefficient along the heated side wall. Computed results showed excellent agreement with experimental data. The flow pattern within the enclosure was found to be quite complex in nature and consisted of a core flow due to forced convection near the central region of the enclosure and strong buoyancy induced flow near the heated side walls. It was found that as the flow rate through the enclosure increased, the enhancement of heat transfer above that for natural convection alone, also increased. The variation of the local heat transfer coefficient over the heated surface was found to be strongly affected by the recirculation of portions of the forced flow within the enclosure as well as the impingement to or separation of flow from the side walls in some regions.

Gao, S.; Rahman, M.M.

1999-07-01T23:59:59.000Z

77

Convective flow and heat transfer of a viscous heat generating fluid in the presence of a moving, infinite, vertical, porous plate  

Science Journals Connector (OSTI)

The analysis of convective flow and heat transfer of a viscous heat generating fluid past a uniformly moving, infinite, vertical, ... of the plate-motion and the presence of heat generation/absorption on the flow...

K. Vajravelu

1978-09-01T23:59:59.000Z

78

PIV flow measurements for heat transfer characterization in two-pass square channels with smooth and 90 ribbed walls  

E-Print Network [OSTI]

PIV flow measurements for heat transfer characterization in two-pass square channels with smooth the correlation between the high- Reynolds number turbulent flow and wall heat transfer characteristics in a two number (Re) of 30,000. The PIV measurement results were compared with the heat transfer experimental data

Kihm, IconKenneth David

79

A method to visualise near wall fluid flow patterns using locally resolved heat transfer experiments  

Science Journals Connector (OSTI)

Abstract The present study demonstrates an alternative approach for describing fluid flow characteristics very close to the wall, using locally resolved convective heat transfer experiments. Heat transfer coefficients on the base surface and around a surface mounted vortex generator of delta-wing shape design, are evaluated with the transient liquid crystal measurement technique and over a range of freestream velocities. Therefore, the local values of exponent m in the equation Nu x ? Re x m , which is directly linked to the structure of the boundary layer, can be determined over the complete heat transfer area. The local distributions of exponent m are then directly compared to the footprint of the flow obtained with typical oil and dye surface flow visualisation. The results indicate that a more appropriate interpretation of the flow structures very close to the wall is possible by analysing the spatial variation of exponent m, which approximates better the flow pattern compared to the heat transfer coefficients. As a result, fluid flow topologies can be directly evaluated from the heat transfer experiments since the distributions of oil-flow visualisation and exponent m are qualitatively similar.

Alexandros Terzis; Jens von Wolfersdorf; Bernhard Weigand; Peter Ott

2015-01-01T23:59:59.000Z

80

Numerical Studies of Fluid Leakage from a Geologic Disposal Reservoir for CO2 Show Self-Limiting Feedback between Fluid Flow and Heat Transfer  

E-Print Network [OSTI]

Feedback between Fluid Flow and Heat Transfer Karsten Pruessfeedback between fluid flow and heat transfer tends to limitfluid mobility (viscosity and relative permeability effects), are countered by effects arising from limitations in the rate of conductive heat transfer.

Pruess, Karsten

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

Experimental study on heat transfer to supercritical water flowing through tubes  

SciTech Connect (OSTI)

A test facility named SWAMUP (Supercritical Water Multi-Purpose Loop) has been constructed in Shanghai Jiao Tong Univ. to investigate heat transfer and pressure drop through tubes and rod bundles. SWAMUP is a closed loop with operating pressure up to 30 MPa, outlet-water temperature up to 550 deg. C, and mass flow rate up to 5 t/h. In this paper, experimental study has been carried out on heat transfer of supercritical water flowing vertically through tubes (ID=7.6 and 10 mm). A large number of test points in tubes has been obtained with a wide range of heat flux (200-1500 kw/m{sup 2}) and mass flux (450-2000 kg/m{sup 2}s). Test results showed that heat transfer deterioration (HTD) caused by buoyancy effect only appears in upward flow and HTD caused by acceleration effect appears both in upward flow and downward flow. The heat transfer coefficients (HTC) produced in tube tests were compared with existing heat transfer correlations. (authors)

Zhao, M.; Gu, H.; Cheng, X. [School of Nuclear Science and Engineering, Shanghai Jiao Tong Univ. SJTU, 800 Dongchuan Road, Shanghai (China)

2012-07-01T23:59:59.000Z

82

Scale effects on flow boiling heat transfer in microchannels: A fundamental perspective  

E-Print Network [OSTI]

pattern transitions and stability for flow boiling of water and FC-77 are evaluated. From the insight between heat transfer around a nucleating bubble in pool boiling and in the elongated bubble/slug flow on the high-speed visualization and localized thermal measurements made at the base of a nucleating bubble

Kandlikar, Satish

83

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

E-Print Network [OSTI]

Computational fluid dynamics Microchannel Minichannel Surface roughness Roughness elements Heat transfer Fluid to achieve enhancement in heat transfer with relatively low cooling fluid flow rate [1]. In spite of havingA numerical study on the effects of 2d structured sinusoidal elements on fluid flow and heat

Kandlikar, Satish

84

EUROTHERM Seminar 74 Proceedings Heat transfer in unsteady and transitional flows March 23-26, 2003 Eindhoven (The Netherlands)  

E-Print Network [OSTI]

EUROTHERM Seminar 74 Proceedings Heat transfer in unsteady and transitional flows March 23-26, 2003 to be governed by heat transfer and time microscales of turbulence through the inner sublayer. Physical interpreta- tions are given to relate the observed heat transfer correlation and these turbulence transition

Paris-Sud XI, Université de

85

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

E-Print Network [OSTI]

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

86

Heat and Mass Transfer in the MHD Flow of a Visco-elastic Fluid in a Rotating Porous Channel with Radiative Heat  

Science Journals Connector (OSTI)

This paper deals with heat and mass transfer in the magnetohydrodynamic flow of a visco-elastic fluid in a rotating porous channel with radiative heat. The flow phenomenon has been characterized by the fluid para...

M. Jena; M. Goswami; S. Biswal

2014-12-01T23:59:59.000Z

87

Numerical simulation of fluid flow and heat transfer in a passage with moving boundary  

Science Journals Connector (OSTI)

In this paper, a method is presented in detail that can be used to solve the fluid flow and heat transfer in domains with moving boundaries. The primitive variables formulation is adopted and a non-staggered grid, with Cartesian velocity components used as the primary unkowns in the momentum equations, is utilised. Discretisation is carried out using a control-volume method, the simplified QUICK scheme combined with a deferred correction approach is adopted for the convective fluxes and implicit time stepping is used for temporal differencing. The well-known SIMPLE algorithm is employed for handling the velocityâ??pressure coupling. The computational method is applied for the prediction of fluid flow and heat transfer in a channel with a boundary moving in a prescribed manner. Results show that both the amplitude and Strouhal number have great influences on the characteristics of fluid flow and heat transfer, and in the range studied, the heat transfer rate increases monotonously with the amplitude, whereas the Strouhal number only has a small effect on heat transfer.

D. S. Zhang; Q. W. Wang; W. Q. Tao

2002-01-01T23:59:59.000Z

88

Flow patterns and heat transfer around six in-line circular cylinders at low Reynolds number  

E-Print Network [OSTI]

The flow field and the heat transfer around six in-line iso-thermal circular cylinders has been studied by mean of numerical simulations. Two values of the center to center spacing ($s=3.6d$ and $4d$, where $d$ is the cylinder diameter) at Reynolds number of $100$ and Prandtl number of $0.7$ has been investigated. Similarly to the in-line two cylinder configuration, in this range a transition in the flow and in the heat transfer occurs. Two different flow patterns have been identified: the stable shear layer (SSL) mode and the shear layer secondary vortices (SLSV) mode, at $3.6$ and $4$ spacing ratio ($s/d$), respectively. At $s/d=3.6$ the flow pattern causes the entrainment of cold fluid on the downstream cylinders enhancing the heat transfer. On the other hand at $s/d=4$ two stable opposite shear layer prevent the cold fluid entrainment over the downstream cylinders reducing their heat exchange. The overall time average heat transfer of the array is enhanced up to 25% decreasing the spacing ratio from $4$ t...

Fornarelli, Francesco; Lippolis, Antonio

2014-01-01T23:59:59.000Z

89

Heat transfer deterioration in tubes caused by bulk flow acceleration due to thermal and frictional influences  

SciTech Connect (OSTI)

Severe deterioration of forced convection heat transfer can be encountered with compressible fluids flowing through strongly heated tubes of relatively small bore as the flow accelerates and turbulence is reduced because of the fluid density falling (as the temperature rises and the pressure falls due to thermal and frictional influence). The model presented here throws new light on how the dependence of density on both temperature and pressure can affect turbulence and heat transfer and it explains why the empirical equations currently available for calculating effectiveness of forced convection heat transfer under conditions of strong non-uniformity of fluid properties sometimes fail to reproduce observed behaviour. It provides a criterion for establishing the conditions under which such deterioration of heat transfer might be encountered and enables heat transfer coefficients to be determined when such deterioration occurs. The analysis presented here is for a gaseous fluid at normal pressure subjected strong non-uniformity of fluid properties by the application of large temperature differences. Thus the model leads to equations which describe deterioration of heat transfer in terms of familiar parameters such as Mach number, Reynolds number and Prandtl number. It is applicable to thermal power plant systems such as rocket engines, gas turbines and high temperature gas-cooled nuclear reactors. However, the ideas involved apply equally well to fluids at supercritical pressure. Impairment of heat transfer under such conditions has become a matter of growing interest with the active consideration now being given to advanced water-cooled nuclear reactors designed to operate at pressures above the critical value. (authors)

Jackson, J. D. [Univ. of Manchester, Manchester (United Kingdom)

2012-07-01T23:59:59.000Z

90

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

E-Print Network [OSTI]

necessary fluid mechanical and heat transfer data forCurvature on Heat Transfer to Incompressible Fluids," Trans.may transfer as much or more heat (to a moving fluid in

Yee, G.

2010-01-01T23:59:59.000Z

91

Heat Transfer in Wedge Flow of a Micropolar Fluid  

Science Journals Connector (OSTI)

The theory of fluids with microstructures was first given by Eringen ... , 1965), and they are called micropolar fluids. These fluids exhibit microrotational effects and microrotational inertia. The flow of such

V. M. Soundalgekar; H. S. Takhar

1980-01-01T23:59:59.000Z

92

Flow and Heat-Transfer Apparatus, Instrumentation and Data Acquisition Method  

E-Print Network [OSTI]

friction and convective heat transfer characteristics of nanofluids. Instead of a usual closed-loop system where pumps and after-cooling units are required, the developed apparatus utilizes nitrogen pressure-driven flow to test a single batch of fluid. This reduces the complexity of the system while improving its

Kostic, Milivoje M.

93

Turbulent models of ice giant internal dynamics: Dynamos, heat transfer, and zonal flows  

E-Print Network [OSTI]

Turbulent models of ice giant internal dynamics: Dynamos, heat transfer, and zonal flows K Magnetic fields a b s t r a c t The ice giant planets, Uranus and Neptune, have magnetic fields to yield small-scale and disorganized turbulence. In agreement with ice giant observations, both

94

5. Heat transfer Ron Zevenhoven  

E-Print Network [OSTI]

1/120 5. Heat transfer Ron Zevenhoven �bo Akademi University Thermal and Flow Engineering / Värme Three heat transfer mechanisms Conduction Convection Radiation 2/120 Pic: B�88 �bo Akademi University | Thermal and Flow Engineering | 20500 Turku | Finland #12;3/120 5.1 Conductive heat transfer �bo Akademi

Zevenhoven, Ron

95

Heat source/sink effects on non-Newtonian MHD fluid flow and heat transfer over a permeable stretching surface: Lie group analysis  

Science Journals Connector (OSTI)

An analysis is performed for flow and heat transfer of a non-Newtonian fluid known as Casson fluid over a permeable stretching surface through a...

M. N. Tufail; A. S. Butt; A. Ali

2014-01-01T23:59:59.000Z

96

Numerical Analysis of Heat Transfer and Fluid Characteristics of Flowing Liquid Nitrogen in HTS Cable  

Science Journals Connector (OSTI)

Abstract High-temperature superconducting (HTS) cable has heat intrusion from the termination including joule heat generation at the terminal joint and from the room temperature cable through the Cu current lead. According to the length of the HTS cable, this heat loss may become a considerable amount which cannot be ignored in the HTS cable system. In this study, referring to a high-voltage cable (HV cable) which was developed in M-PACC project, the effect of heat transfer at the interface between the terminal joint and LN2 in the terminal vessel (ho) on the temperature of the HTS cable were calculated and evaluated. The condition of flow in the terminal vessel was assumed to be natural convection, forced flow or static condition for evaluating this effect with various heat transfer condition. As a result, in the case of the natural convection, most of heats flow into the LN2 in the terminal vessel where the volumetric flow of the LN2 is large since ho becomes high. Accordingly, the temperature rise of the LN2 in the inner pipe of Cu former and the terminal vessel can be restricted. However, in the cases of the forced flow and the static condition, most of heats flow into the LN2 in the inner pipe where the volumetric flow of the LN2 is small since ho becomes small. Accordingly, the temperature rise of the LN2 in the inner pipe becomes high. This temperature rise of the LN2 in the inner pipe makes the temperature of the HTS conductor large resulting in remarkable increase of AC losses. Consequently, on the HV cable design, for restriction of the AC loss increase, it is expected that designing the HTS cable termination such as extending outer surface of the terminal joint for increasing of the heat inflow from the terminal joint to the LN2 in the vessel is effective.

O. Maruyama; T. Ohkuma; T. Izumi; Y. Shiohara

2014-01-01T23:59:59.000Z

97

Effect of heat transfer on the plane-channel poiseuille flow of a thermo-viscous fluid  

Science Journals Connector (OSTI)

A steady-state plane channel flow of viscous incompressible fluid with no-slip and heat transfer boundary conditions is considered. The flow is ... induced by a fixed pressure difference and the fluid viscosity d...

S. N. Aristov; V. G. Zelenina

98

Turbulent heat transfer in a channel flow at transitional Reynolds numbers  

E-Print Network [OSTI]

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

Tsukahara, Takahiro

2014-01-01T23:59:59.000Z

99

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...

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

2006-01-01T23:59:59.000Z

100

Three-dimensional analysis of fluid flow and heat transfer in single- and two-layered micro-channel heat sinks  

Science Journals Connector (OSTI)

A three-dimensional numerical analysis of laminar fluid flow and conjugate heat transfer has been conducted for single- and two-layered micro-channel heat sinks. The validity of the numerical model ... power, the...

M. L.-J. Levac; H. M. Soliman; S. J. Ormiston

2011-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

Heat and mass transfer in a visco–elastic fluid flow over an accelerating surface with heat source/sink and viscous dissipation  

Science Journals Connector (OSTI)

...?In this paper we present a mathematical analysis of heat and mass transfer phenomena in a visco–elastic fluid flow over an accelerating stretching sheet in the presence of heat source/sink, viscous dissipatio...

R. M. Sonth; S. K. Khan; M. S. Abel; K. V. Prasad

2002-02-01T23:59:59.000Z

102

Review of fluid flow and convective heat transfer within rotating disk cavities with impinging jet  

E-Print Network [OSTI]

Fluid flow and convective heat transfer in rotor-stator configurations, which are of great importance in different engineering applications, are treated in details in this review. The review focuses on convective heat transfer in predominantly outward air flow in the rotor-stator geometries with and without impinging jets and incorporates two main parts, namely, experimental/theoretical methodologies and geometries/results. Experimental methodologies include naphthalene sublimation techniques, steady state (thin layer) and transient (thermochromic liquid crystals) thermal measurements, thermocouples and infra-red cameras, hot-wire anemometry, laser Doppler and particle image velocimetry, laser plane and smoke generator. Theoretical approaches incorporate modern CFD computational tools (DNS, LES, RANS etc). Geometries and results part being mentioned starting from simple to complex elucidates cases of a free rotating disk, a single disk in the crossflow, single jets impinging onto stationary and rotating disk,...

Harmand, Souad; Poncet, Sébastien; Shevchuk, Igor V; 10.1016/j.ijthermalsci.2012.11.009

2013-01-01T23:59:59.000Z

103

Boundary layer flow and heat transfer analysis of a second-grade fluid  

SciTech Connect (OSTI)

Boundary layer flow and heat transfer analysis of a homogeneous, incompressible, non-Newtonian fluid of grade two at a stagnation point is presented. The flow is assumed to be steady and laminar. A power-law representation is assumed for the velocity distribution and wall temperature variation. The governing equations are solved using an iterative central difference approximation method in a non-uniform grid domain. This analysis show the effect of non-Newtonian nature of the fluid and the effect of suction/injection on the velocity profile. The effect of non-Newtonian nature of the fluid on the heat transfer coefficient at the wall for different values of Prandtl number and wall-temperature variation is also presented. (VC)

Massoudi, M. [USDOE Pittsburgh Energy Technology Center, PA (United States); Ramezan, M. [Burns and Roe Services Corp., Pittsburgh, PA (United States)

1992-04-01T23:59:59.000Z

104

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

SciTech Connect (OSTI)

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

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

2012-07-01T23:59:59.000Z

105

Numerical study of fluid flow and heat transfer characteristics in an intermittent turbulent impinging round jet  

Science Journals Connector (OSTI)

Abstract The flow structure and heat transfer of the air pulsed turbulent impinging jet are studied numerically. The gas turbulence is modelled with the Reynolds stress model. The effects of pulse frequency, ratio of on time to total cycle time, distance between pipe outlet and impinging flat plate and Reynolds number on heat transfer are numerically studied. The impingement heat transfer increases with distance from the pipe edge and target surface. The heat transfer decreases at high distance from the pipe edge and target surface. An increase in the Reynolds number causes reduction of heat transfer enhancement. Reduced heat transfer in comparison with the steady-state impinging jet is typical in the range of low frequencies of the pulse impinging jet.

M.A. Pakhomov; V.I. Terekhov

2015-01-01T23:59:59.000Z

106

Flow and heat transfer from a continuous surface in a parallel free stream of viscoelastic second-order fluid  

Science Journals Connector (OSTI)

Boundary layer solutions are presented to investigate the steady flow and heat transfer characteristics from a continuous flat surface moving in a parallel free stream of viscoelastic fluid. Numerical results are...

I. A. Hassanien

1992-10-01T23:59:59.000Z

107

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

E-Print Network [OSTI]

A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN GREENDYKE Submitted to the Graduate College of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August 1988 Major Subject: Aerospace Engineering A PARAMETRIC STUDY OF SHOCK JUMP CHEMISTRY, ELECTRON TEMPERATURE, AND RADIATIVE HEAT TRANSFER MODELS IN HYPERSONIC FLOWS A Thesis by ROBERT BRIAN...

Greendyke, Robert Brian

2012-06-07T23:59:59.000Z

108

The influence of convective heat transfer on flow stability in rotating disk chemical vapor deposition reactors  

SciTech Connect (OSTI)

Flow and heat transfer of NH{sub 3} and He were studied in a rotating disk system with applications to chemical vapor deposition reactors. Flow field and disk heat flux were obtained over a range of operating conditions. Comparisons of disk convective heat transfer were made to infinite rotating disk results to appraise uniformity of transport to the disk. Important operating variables include disk spin rate, disk and enclosure temperatures, flow rate, composition, pressure, and gas mixture temperature at the reactor inlet. These variables were studied over ranges of the spin Reynolds number, Re{omega}; disk mixed convection parameter, MCP{sub w}; and wall mixed convection parameter, MCP{sub w}. Results obtained for NH{sub 3} show that increasing Re{omega} from 314.5 to 3145 increases the uniformity of rotating disk heat flux and results in thinner thermal boundary layers at the disk surface. At Re{omega}=314.5, increasing MCP{sub d} to 15 leads to significant departure from the infinite disk result with nonuniform disk heat fluxes and recirculating flow patterns; flow becomes increasingly complex at larger values of MCP{sub d}. At Re{omega} of 3145, results are closer to the infinite disk for MCP{sub d} up to 15. For large negative (hot walls) and positive (cold walls) values of MCP{sub w}, flow recirculates and there is significant deviation from the infinite disk result; nonuniformities occur at both values of Re{omega}. The influence of MCP{sub w} on flow stability is increased at larger MCP{sub d} and lower Re{omega}. To determine the influence of viscosity and thermal conductivity variation with temperature, calculations were made with He and NH{sub 3}; He transport property variation is low relative to NH{sub 3}. Results show that the flow of NH{sub 3} is less stable than that of He as MCP{sub d} is increased for MCP{sub w}=0 and Re{omega}=314.5. 16 refs., 15 figs., 1 tab.

Winters, W.S.; Evans, G.H. [Sandia National Labs., Livermore, CA (United States); Grief, R. [Univ. of California, Berkeley, CA (United States). Mechanical Engineering Dept.

1997-06-01T23:59:59.000Z

109

Heat transfer enhancement on thin wires in superfluid helium forced flows  

E-Print Network [OSTI]

In this paper, we report the first evidence of an enhancement of the heat transfer from a heated wire by an external turbulent flow of superfluid helium. We used a standard Pt-Rh hot-wire anemometer and overheat it up to 21 K in a pressurized liquid helium turbulent round jet at temperatures between 1.9 K and 2.12 K. The null-velocity response of the sensor can be satisfactorily modeled by the counter flow mechanism while the extra cooling produced by the forced convection is found to scale similarly as the corresponding extra cooling in classical fluids. We propose a preliminary analysis of the response of the sensor and show that -contrary to a common assumption- such sensor can be used to probe local velocity in turbulent superfluid helium.

Duri, Davide; Moro, Jean-Paul; Roche, Philippe-Emmanuel; Diribarne, Pantxo

2014-01-01T23:59:59.000Z

110

Heat transfer in channels with porous inserts during forced fluid flow  

Science Journals Connector (OSTI)

General analytic expressions are obtained to calculate heat transfer and temperature fields in a plane channel ... allowance for the effective thermal conductivity of the heat carrier and the distribution of heat

A. A. Plakseev; V. V. Kharitonov

1989-01-01T23:59:59.000Z

111

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

E-Print Network [OSTI]

of Fracture-Matrix Heat Transfer Jens T. Birkholzer andon the magnitude of heat transfer from the matrix, waterthe interface area for heat transfer between the matrix and

Birkholzer, Jens T.; Zhang, Yingqi

2005-01-01T23:59:59.000Z

112

Heat transfer during the flow of an incompressible fluid in a circular tube, allowing for axial heat flow, with boundary conditions of the first and second kind at the tube surface  

Science Journals Connector (OSTI)

An examination is made of heat transfer in a hydraulically stabilized laminar stream and in a two-layer dynamic flow model.

V. V. Shapovalov

1966-09-01T23:59:59.000Z

113

On numerical simulation of flow, heat transfer and combustion processes in tangentially-fired furnace  

SciTech Connect (OSTI)

In this work, an Eulerian/Lagrangian approach has been employed to investigate numerically flow characteristics, heat transfer and combustion processes inside corner-fired power plant boiler furnace. To avoid pseudo-diffusion that is significant in modeling tangentially-fired furnaces, some attempts have been made at improving the finite-difference scheme. Comparisons have been made between standard {kappa}-{epsilon} model and RNG {kappa}-{epsilon} model. Some new developments on turbulent diffusion of particles are taken into account in an attempt to improve computational accuracy. Finally, temperature deviation is studied numerically so as to gain deeper insight into tangentially fired furnace.

Sun, P.; Fan, J.; Cen, K.

1999-07-01T23:59:59.000Z

114

Heat transfer in the flow of a cold, axisymmetric jet over a hot sphere  

E-Print Network [OSTI]

The heat transfer characteristics of thin film flow over a hot sphere resulting from a cold vertical jet of liquid falling onto the surface has been investigated. The underlying physical features have been illustrated by numerical solutions of high accuracy based on the modified Keller box method. The solutions for film thickness distribution are good agreement with those obtained approximately by using the Pohlhausen integral momentum technique and observed experimentally by using water as working fluid, thus providing a basic confirmation of the validity of the results presented.

Shu, Jian-Jun

2014-01-01T23:59:59.000Z

115

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

E-Print Network [OSTI]

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

Fullerton, Tracy

2012-02-14T23:59:59.000Z

116

Characteristics of fluid flow and heat transfer in a fluidized heat exchanger with circulating solid particles  

Science Journals Connector (OSTI)

The commercial viability of heat exchanger is mainly dependent on its long- ... loss and degrades the thermal performance of a heat exchanger. An experimental study was performed to investigate the characteristic...

Soo Whan Ahn; ByungChang Lee; WonCheol Kim; Myung- Whan Bae…

2002-09-01T23:59:59.000Z

117

Numerical Analysis of Fluid Flow and Heat Transfer within Grooved Flat Mini Heat Pipes  

Science Journals Connector (OSTI)

A Theoretical study is carried out in order to verify the Mini Heat Pipe (MHP) concept for cooling high ... as an integrated part of a Flat Mini Heat Pipe (FMHP). Hence, a detailed ... with axial microchannels is...

Jed Mansouri; Samah Maalej; Mohamed Sassi…

2013-01-01T23:59:59.000Z

118

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

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

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

119

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

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

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

120

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

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

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

Note: This page contains sample records for the topic "flow heat transfer" 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

On the calculation of flow and heat transfer characteristics for CANDU-type 19-rod fuel bundles  

SciTech Connect (OSTI)

A numerical study is reported of flow and heat transfer in a CANDU-type 19 rod fuel bundle. The flow domain of interest includes combinations of trangular, square, and peripheral subchannels. The basic equations of momentum and energy are solved with the standard k--epsilon model of turbulence. Isotropic turbulent viscosity is assumed and no secondary flow is considered for this steady-state, fully developed flow. Detailed velocity and temperature distributions with wall shear stress and Nusselt number distributions are obtained for turbulent flow of Re = 4.35 x 10/sup 4/, 10/sup 5/, 2 x 10/sup 5/, and for laminar flow of Re--2400. Friction factor and heat transfer ceofficients of various subchannels inside the full bundle are compared with those of infinite rod arrays of triangular or square arrangements. The calculated velocity contours of peripheral subchannel agreed reasonably with measured data.

Yuh-Shan Yueh; Ching-Chang Chieng

1987-08-01T23:59:59.000Z

122

On the calculation of flow and heat transfer characteristics for CANDU-type 19-rod fuel bundles  

SciTech Connect (OSTI)

A numerical study is reported of flow and heat transfer in a CANDU-type 19 rod fuel bundle. The flow domain of interest includes combinations of triangular, square, and peripheral subchannels. The basic equations of momentum and energy are solved with the standard k-{epsilon} model of turbulence. Isotropic turbulent viscosity is assumed and no secondary flow is considered for this steady-state, fully developed flow. Detailed velocity and temperature distributions with wall shear stress and Nusselt number distributions are obtained for turbulent flow of Re = 4.35 {times} 10{sup 4}, 10{sup 5}, 2 {times} 10{sup 5}, and for laminar flow of Re {approximately} 2,400. Friction factor and heat transfer coefficients of various subchannels inside the full bundle are compared with those of infinite rod arrays of triangular or square arrangements. The calculated velocity contours of peripheral subchannel agreed reasonably with measured data.

Yueh, Yuhshan; Chieng, Chingchang (National Tsing Hua Univ., Hsinchu (Taiwan))

1987-08-01T23:59:59.000Z

123

A numerica1 study of fluid flow and heat transfer in different microchannel heat sinks for electronic chip cooling  

Science Journals Connector (OSTI)

Four different microchannel heat sinks are designed to study the effects of structures in microchannel heat sinks for electronic chips cooling. Based on the theoretic analysis and numerical computation of flow...

Shanglong Xu; Guangxin Hu; Jie Qin…

2012-04-01T23:59:59.000Z

124

Convective heat transfer enhancement of laminar flow of latent functionally thermal fluid in a circular tube with constant heat flux: internal heat source model and its application  

Science Journals Connector (OSTI)

This paper analyzes the convective heat transfer enhancement mechanism of latent heat functionally thermal fluid. By using the proposed internal heat source model, the influence of each factor affecting the heat

Yinping Zhang; Xianxu Hu; Qing Hao; Xin Wang

2003-04-01T23:59:59.000Z

125

HEAT TRANSFER FLUIDS  

E-Print Network [OSTI]

The choice of heat transfer fluids has significant effects on the performance, cost, and reliability of solar thermal systems. In this chapter, we evaluate existing heat transfer fluids such as oils and molten salts based ...

Lenert, Andrej

2012-01-01T23:59:59.000Z

126

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

127

Numerical Simulation of Heat Transfer and Fluid Flow Characteristics of Server Rack in Datacenter  

Science Journals Connector (OSTI)

This chapter is studying the fluid mechanics and heat transfer of single server rack using the computational fluid dynamics software. The ... effect of the different structure parameters of server rack in datacen...

Jianfei Zhang; Donghao Liu; Xiping Qiao…

2014-01-01T23:59:59.000Z

128

Computational Analysis of Fluid Flow and Heat Transfer Characteristics of Obliquely Impinging Slot Jets  

Science Journals Connector (OSTI)

The skin friction and heat transfer characteristics due to a slot jet impinging obliquely on a flat plate are presented. The boundary layer equations are solved by a finite difference marching technique, detai...

S. Jayaraj; Vijay K. Garg

1988-01-01T23:59:59.000Z

129

Summary of Modern Nodal Integral Methods in Fluid Flow and Heat Transfer  

Science Journals Connector (OSTI)

Modern nodal integral methods are a product of original applications in neutron diffusion and neutron transport calculations. These methods have recently been applied to two-dimensional dynamic heat transfer and

G. L. Wilson; R. A. Rydin

1990-01-01T23:59:59.000Z

130

Heat Transfer Guest Editorial  

E-Print Network [OSTI]

Journal of Heat Transfer Guest Editorial We are indeed delighted in bringing out this special issue was showcased in diverse areas such as traditional heat and mass transfer, lab-on-chip, sensors, biomedical applica- tions, micromixers, fuel cells, and microdevices. Selected papers in the field of heat transfer

Kandlikar, Satish

131

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

E-Print Network [OSTI]

COMMANDS . . APPENDIX C: UNCERTAINTY ANALYSIS . APPENDIX D: RAW DATA & RESULTS . . 71 . . . . 74 77 VITA. 134 vu1 LIST OF FIGURES Page Figurc 1 Internal and external cooling concepts used in modem gas turbine airfoils (Han et al. ). Figure 2... . . . . . . . . . . . . . . . . . . . . . . . . . 62 xt NOMENCLATURE A, flow cross-sectional area of test channel, m 2 surface area, m 2 D?hydraulic diameter of test channel, m friction factor f, reference friction factor for fully developed turbulent flow in smooth channel heat transfer...

Cervantes, Joel

2012-06-07T23:59:59.000Z

132

Convective Heat Transfer and Fluid Dynamics in Heat Exchanger Applications  

Science Journals Connector (OSTI)

This article concerns the local structure of flow and temperature fields as well as overall heat transfer coefficients and pressure drops in flow passages of relevance for heat exchangers. Results from investi...

Bengt Sundén

1999-01-01T23:59:59.000Z

133

Heat and mass transfer on MHD heat generating flow through a porous medium in a rotating fluid  

Science Journals Connector (OSTI)

The problem of the free-convection flow of a viscous heat generating fluid through porous media in a rotating frame of reference is considered for the case when a strong magnetic field is imposed in a directio...

P. C. Ram

134

DNS on turbulent heat transfer of viscoelastic fluid flow in a plane channel with transverse rectangular orifices  

Science Journals Connector (OSTI)

Heat-transfer characteristics of a viscoelastic turbulence past rectangular orifices were investigated in the context of the reduction effects of fluid elasticity on drag and heat transfer. To simulate the fully-developed channel flow through transverse orifices located periodically at intervals of 6.4 times channel height, we imposed periodic conditions at the upstream and downstream boundaries. To discuss the dissimilarity between the velocity and thermal fields, the molecular Prandtl number was set to be 1.0 and any temperature dependence of the fluid and rheological properties was not considered. In the present condition, the ratio of the reduction rates in drag and heat transfer was found to be 2.8:1.0, revealing that the present flow configuration is better than a smooth channel for avoiding the heat-transfer reduction. This phenomenon was attributed to the sustainment of the quasi-streamwise vortex downstream of the reattachment point despite the absence of strong spanwise vortices emanating from the orifice edge in the viscoelastic fluid. The longitudinal vortices behind the reattachment point caused a high turbulent heat flux and increased the local Nusselt number.

Takahiro Tsukahara; Tomohiro Kawase; Yasuo Kawaguchi

2013-01-01T23:59:59.000Z

135

Evaporation heat transfer and friction characteristics of R-134a flowing downward in a vertical corrugated tube  

SciTech Connect (OSTI)

Differently from most previous studies, the heat transfer and friction characteristics of the pure refrigerant HFC-134a during evaporation inside a vertical corrugated tube are experimentally investigated. The double tube test sections are 0.5 m long with refrigerant flowing in the inner tube and heating water flowing in the annulus. The inner tubes are one smooth tube and two corrugated tubes, which are constructed from smooth copper tube of 8.7 mm inner diameter. The test runs are performed at evaporating temperatures of 10, 15, and 20 C, heat fluxes of 20, 25, and 30 kW/m{sup 2}, and mass fluxes of 200, 300, and 400 kg/m{sup 2} s. The quality of the refrigerant in the test section is calculated using the temperature and pressure obtained from the experiment. The pressure drop across the test section is measured directly by a differential pressure transducer. The effects of heat flux, mass flux, and evaporation temperature on the heat transfer coefficient and two-phase friction factor are also discussed. It is found that the percentage increases of the heat transfer coefficient and the two-phase friction factor of the corrugated tubes compared with those of the smooth tube are approximately 0-10% and 70-140%, respectively. (author)

Aroonrat, Kanit; Wongwises, Somchai [Fluid Mechanics, Thermal Engineering and Multiphase Flow Research Lab. (FUTURE), Department of Mechanical Engineering, King Mongkut's University of Technology Thonburi, Bangmod, Bangkok 10140 (Thailand)

2011-01-15T23:59:59.000Z

136

The flow and heat transfer characteristics of multi-thermal fluid in horizontal wellbore coupled with flow in heavy oil reservoirs  

Science Journals Connector (OSTI)

Abstract As a new improved oil-recovery technique, multi-thermal fluid injection technology through a horizontal well has been widely used in the development process of heavy oil reservoirs. The flow and heat transfer characteristic of multi-thermal fluid in horizontal wellbore is significantly important for the productivity evaluation and parameters design of the horizontal well. Considering the specific physical properties of multi-thermal fluid, fluid absorption in perforation holes and pressure drop characteristics along the horizontal wellbore, this paper developed the flow and heat transfer model of multi-thermal fluid in perforated horizontal wellbore. In order to evaluate the heating effect of the multi-thermal fluid, a concept of effective heating length of a horizontal well is proposed. Then, a sensitivity analysis process is performed to study the influence of reservoir/fluid parameters and operating parameters on the flowing process of multi-thermal fluid in horizontal wellbore. Simultaneously, using the method of orthogonal numerical test, differential analysis and variance analysis are also conducted. Results show that the flowing process of multi-thermal fluid in horizontal wellbore includes a single-phase flowing process and a gas–liquid two-phase flowing process. The influence of oil viscosity on the flow and heat transfer characteristics of multi-thermal fluid in horizontal wellbore is most significant. Thereafter, the solution of our semi-analytical model is compared against the test results of an actual horizontal well from an oilfield in China. It is shown that the model results are in good agreement with the real test results. This model could be used to calculate and predict the flow and heat transfer characteristics of multi-thermal fluid (or saturated steam) in a perforated horizontal wellbore.

Xiaohu Dong; Huiqing Liu; Zhaoxiang Zhang; Changjiu Wang

2014-01-01T23:59:59.000Z

137

On the multidimensional modeling of fluid flow and heat transfer in SCWRS  

SciTech Connect (OSTI)

The Supercritical Water Reactor (SCWR) has been proposed as one of the six Generation IV reactor design concepts under consideration. The key feature of the SCWR is that water at supercritical pressures is used as the reactor coolant. Although at such pressures, fluids do not undergo phase change as they are heated, the fluid properties experience dramatic variations throughout what is known as the pseudo-critical region. Highly nonuniform temperature and fluid property distributions are expected in the reactor core, which will have a significant impact on turbulence and heat transfer in future SCWRs. The goal of the present work has been to understand and predict the effects of these fluid property variations on turbulence and heat transfer throughout the reactor core. Spline-type property models have been formulated for water at supercritical pressures in order to include the dependence of properties on both temperature and pressure into a numerical solver. New models of turbulence and heat transfer for variable-property fluids have been developed and implemented into the NPHASE-CMFD software. The results for these models have been compared to experimental data from the Korea Atomic Energy Research Inst. (KAERI) for various heat transfer regimes. It is found that the Low-Reynolds {kappa}-{epsilon} model performs best at predicting the experimental data. (authors)

Gallaway, T.; Antal, S. P.; Podowski, M. Z. [Center for Multiphase Research, Rensselaer Polytechnic Inst., 110 8th St., Troy, NY (United States)

2012-07-01T23:59:59.000Z

138

Numerical analysis of convective heat transfer characteristics of supercritical hydrocarbon fuel in cooling panel with local flow blockage structure  

Science Journals Connector (OSTI)

Abstract The convection heat transfer of hydrocarbon fuel at supercritical pressure has a great influence on the regenerative cooling technology of a scramjet engine. A three-dimensional numerical simulation was conducted for the convection transfer of hydrocarbon fuel in the cooling panel of a combustion chamber wall. And the flow field around the local flow blockage structure and the outlet flow rate distribution characteristics of fuel in the cooling channels were analyzed in detail. The results of analyses indicate that with the optimized local flow blockage structure, the outlet flow rate distribution of fuel among the cooling channels become more uniform, as the area of local flow dead zone decreases. However, as the fuel temperature increases, the dramatic variation of thermodynamic physical properties of fuel has a strong influence on the flow field around the local flow blockage structure. Especially, a local flow dead zone can be easily formed in the supercritical temperature region. Meanwhile, transverse pressure gradient around the throat region of blockage structure and additional loss, which is caused by turbulence fluctuation and energy exchange of fluid in the downstream area, affect the outlet flow rate distribution of fuel among the coolant passages seriously. It can therefore be concluded that the local flow blockage structure is more suitably designed in the subcritical temperature region by taking above-mentioned factors into consideration.

Yu Feng; Jiang Qin; Wen Bao; Qinchun Yang; Hongyan Huang; Zhongqi Wang

2014-01-01T23:59:59.000Z

139

Internal Heat Transfer Coefficient Determination in a Packed Bed From the Transient Response Due to Solid Phase Induction Heating  

E-Print Network [OSTI]

equations governing fluid flow and heat transfer in porousParticle-to-Fluid Heat and Mass Transfer in Packed Beds,”Systems,” Experimental Heat Transfer, Fluid Mechanics and

Geb, David; Zhou, Feng; Catton, Ivan

2012-01-01T23:59:59.000Z

140

Effects of the ship motion on gas–solid flow and heat transfer in a circulating fluidized bed  

Science Journals Connector (OSTI)

A series of experiments on a circulating fluidized bed (CFB) was performed to investigate the effects of ship motion on gas–solid flow and heat transfer in the CFB. Rolling period, rolling amplitude, inclination angle, superficial velocity, particle diameter range, and solid circulation flux were varied in the experiments. The following results were obtained: (1) When the CFB undergoes rolling motion, the downflow of particles changes periodically and the solid volume fraction increases at the riser bottom. As a result, the time-averaged total pressure drop of the CFB in rolling motion becomes larger than that at the upright attitude. Similarly, the total pressure drop of the CFB at an inclined attitude is larger than that at the upright attitude. (2) The total pressure drop of the CFB in rolling motion is hardly affected by rolling period. As rolling amplitude increases, on the other hand, the effects of rolling motion become more remarkable. From these results, it is concluded that gravity dominantly affects gas–solid flow in the system. (3) At an inclined attitude, the symmetry of the flow field with respect to the riser center plane breaks, and heat transfer at the lower wall of the riser is promoted. As inclination angle increases, heat transfer augmentation becomes more remarkable. Similarly, the heat transfer coefficient in rolling motion is larger than that at the upright attitude. (4) Heat transfer augmentation by ship motion is concluded to be caused by the direct contact between solid particles and the heater surface owing to the vertical component of gravity to the surface.

Hiroyuki Murata; Hideyuki Oka; Masaki Adachi; Kazuyoshi Harumi

2012-01-01T23:59:59.000Z

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


141

Heat transfer dynamics  

SciTech Connect (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

142

Heat transfer process under a film-cooled surface with presence of weak swirling flow in the mainstream  

SciTech Connect (OSTI)

Experiments have been performed in a relatively large circular pipe to study and obtain the heat transfer data over a film-cooled surface, with the presence of weak swirling flow in the mainstream. The swirling flow is generated by a flat-vaned swirler situated upstream. A cooling film is injected from an annular slot formed by the pipe wall and the circular cover plate. The radial temperature distribution measurements at several axial locations were used to infer the film jet structure and the rate of mixing of the film jet with the swirling flow. The nondimensional parameters governing the heat transfer process under the film are derived from the system of governing equations. Experiments demonstrate that the swirl number, increasing with turbulence intensity and swirl velocity in the mainstream, can rapidly destroy the film jet structure and enhance the heat transfer process. During the course of the experiments, the blowing parameter ranged from 0.5 to 2 and the swirl number ranged from 0 to 0.6. Correlations for the Nusselt number which account for the effect of swirling flow are presented. (author)

Yang, C.S. [Department of Computer Science and Information Engineering, Far East University, Tainan (China); Kung, T.L.; Gau, C. [Institute of Aeronautics and Astronautics, Center for Micro/Nano Science and Technology, National Cheng Kung University (China)

2007-11-15T23:59:59.000Z

143

Mixed convection flow and heat transfer in entrance region of rectangular ducts rotating about a parallel axis  

SciTech Connect (OSTI)

The objective of the present work is to investigate the laminar mixed convection flow and heat transfer in the entrance region of heated rectangular ducts rotating about a parallel axis. Heating conditions of isothermal and iso-flux are both considered. Boussinesq approximation is invoked to take into account buoyancy effect induced by centrifugal force. Navier-Stokes/Boussinesq system can be cast into a dimensionless form, in which five governing parameters, the Prandtl number Pr, rotational Reynolds number J, rotational Grashof number Gr{sub {Omega}}, aspect ratio {gamma} and the eccentricity E, are involved. Mechanisms of secondary vortex development in the ducts are explored by a theoretical analysis on vorticity transport equation. The values of Pr and E are fixed as 0.7 and 10, respectively. For various combinations of the other thee parameters, a vorticity-velocity method implemented with a marching technique is employed to solve the resultant three-dimensional system for simultaneously developing flow and temperature fields. The emphasis is placed on the rotational effects, including both coriolis force and centrifugal buoyancy; on the non-isothermal flow and the related heat transfer. The results reveal that the friction factors and heat transfer rates can be enhanced by Coriolis and rotation-induced buoyancy effects; and the variations of the local values are closely related to the evolution of the secondary vortices in ducts. The differences in flow behaviors and thermal characteristics for UWT and UHF are also investigated by the present theoretical analysis on secondary flow mechanism as well as the computational results.

Soong, C.Y. [Chung Cheng Inst. of Tech., Taoyuan (Taiwan, Province of China). Dept. of Aeronautical Engineering; Yan, W.M. [Hua Fan Coll. of Humanities and Technology, Taipei (Taiwan, Province of China). Dept. of Mechanical Engineering

1995-12-31T23:59:59.000Z

144

Heat transfer and temperature distribution in a turbulent flow over a flat plate with an unheated starting length  

SciTech Connect (OSTI)

The present study is a numerical investigation of heat transfer and temperature distribution in a boundary layer formed by a flow with nonzero free stream turbulence over a flat plate with an unheated starting length. The numerical method is based on the Reynolds-averaged equations of motion and energy. As a closure for the Reynolds- averaged equations the Hinze relations for turbulent shear stresses and for turbulent heat flux are used. The Hinze equations are used instead of the usually employed Boussinesq eddy-viscosity hypothesis, because the latter does not work properly for flows with high free stream turbulence. It is shown in the present study that the influence of an unheated starting length on a temperature profile has manifested itself similarly to the influence of the free stream turbulence and resulted in a temperature profile with negative profile parameter. Unlike the flow with zero free stream turbulence, a heat transfer coefficient for the part of the plate with an unheated starting length can be less than for the fully heated plate. This difference increases with increasing level of the free stream turbulence. The family of functions that describe the influence of an unheated starting length for flows with nonzero free stream turbulence is presented.

Fridman, E.

1997-07-01T23:59:59.000Z

145

Heat transfer and fluid flow in microchannels and nanochannels at high Knudsen number using thermal lattice-Boltzmann method  

Science Journals Connector (OSTI)

The present paper deals with the two-dimensional numerical simulation of gaseous flow and heat transfer in planar microchannel and nanochannel with different wall temperatures in transitional regime 0.1?Kn?1. An atomistic molecular simulation method is used known as thermal lattice-Boltzmann method. The results of simulation are presented in four cases corresponding to the Fourier flow, shear-driven flow (Couette flow), pressure-driven flow (Poiseuille flow), and mixed shear–pressure-driven flow in the developing and fully developed regions. The mixed shear–pressure-driven flow is divided into two subcases with shear stress and pressure gradient acting in the same and the opposite directions. Normalized temperature and velocity profiles across the channel, distribution of local wall Nusselt number, and friction coefficient are illustrated. Using this method, nonlinear pressure distribution in the streamwise direction, reduction in mass flow rate, Cf?Re, and Nu by increasing the Knudsen number are studied. It is seen that for Couette flow, Nu over the hotter plate is greater than the cooler plate, but for the pressure-driven flow with stationary wall temperature dependency of viscosity and thermal conductivity causes this trend to be reversed. The reversed flow appearance in the velocity profile is captured in the case of opposite shear–pressure-driven flow.

J. Ghazanfarian and A. Abbassi

2010-08-13T23:59:59.000Z

146

Solutions of turbulent backward-facing step flow with heat transfer using the finite volume method  

SciTech Connect (OSTI)

The heated turbulent flow over a backward-facing step is numerically solved using the commercial computational fluid dynamics program FLUENT. The methods used here consist of the default power-law upwinding scheme, default multigrid equation solution method and a standard k-{var_epsilon} turbulence model with wall functions. A total of four separate cases are reported. The four cases consist of combinations of partially and fully developed flow at the inlet with uniform or developed temperature profiles. Three mesh refinements are reported for each flow.

Horstman, R.H. [Boeing Commercial Airplane, Seattle, WA (United States). Environmental Control Systems R& D; Cochran, R.J. [Sandia National Labs., Albuquerque, NM (United States); Emergy, A.F. [Univ. of Washington, Seattle, WA (United States). Dept. of Mechanical Engineering

1995-12-31T23:59:59.000Z

147

Flow and Heat Transfer of a MHD Viscoelastic Fluid in a Channel with Stretching Walls: Some Applications to Haemodynamics  

E-Print Network [OSTI]

Of concern in the paper is a study of steady incompressible viscoelastic and electrically conducting fluid flow and heat transfer in a parallel plate channel with stretching walls in the presence of a magnetic field applied externally. The flow is considered to be governed by Walter's liquid B fluid. The problem is solved by developing a suitable numerical method. The results are found to be in good agrement with those of earlier investigations reported in existing scientific literatures. The study reveals that a back flow occurs near the central line of the channel due to the stretching walls and further that this flow reversal can be stopped by applying a strong external magnetic field. The study also shows that with the increase in the strength of the magnetic field, the fluid velocity decreases but the temperature increases. Thus the study bears potential applications in the study of the haemodynamic flow of blood in the cardiovascular system when subjected to an external magnetic field.

Misra, J C; Rath, H J

2010-01-01T23:59:59.000Z

148

Numerical studies for flow and heat transfer of the Powell-Eyring fluid thin film over an unsteady stretching sheet with internal heat generation using the chebyshev finite difference method  

Science Journals Connector (OSTI)

An analysis is carried out to study the unsteady two-dimensional Powell-Eyring flow and heat transfer to a laminar liquid film from a ... horizontal stretching surface in the presence of internal heat generation....

M. M. Khader; A. M. Megahed

2013-05-01T23:59:59.000Z

149

Experimental and numerical investigation of turbulent flow and heat (mass) transfer in a two-pass trapezoidal channel with turbulence promoters  

E-Print Network [OSTI]

of three-dimensional flow and heat transfer also were performed for the trapezoidal channel with and without 90º ribs tested by Lee et al. (2007). Reynolds stress turbulence model (RSM) in the FLUENT CFD code was used to calculate the heat transfer...

Oh, Sung Hyuk

2009-05-15T23:59:59.000Z

150

Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference  

E-Print Network [OSTI]

Proceedings of Heat Transfer 2003: ASME Summer Heat Transfer Conference Las Vegas, Nevada, USA July 21-23, 2003 HT2003-47449 HEAT TRANSFER FROM A MOVING AND EVAPORATING MENISCUS ON A HEATED SURFACE meniscus with complete evaporation of water without any meniscus break-up. The experimental heat transfer

Kandlikar, Satish

151

Study of Heat Transfer in Non-boiling Two-phase Gas-liquid Flow in Pipes for Horizontal, Slightly Inclined, and Vertical Orientations.  

E-Print Network [OSTI]

??The main objective of this research is to establish a fundamental understanding of heat transfer in non-boiling two-phase pipe flow. The key processes that govern… (more)

Tang, Clement Chih-Wei

2011-01-01T23:59:59.000Z

152

Convective heat transfer in the vertical channel flow of a clear fluid adjacent to a nanofluid layer: a two-fluid model  

Science Journals Connector (OSTI)

A two-fluid vertical channel flow and convective heat transfer model in which one of the two fluids is a nanofluid demonstrates that the nanofluid can modify the fluid velocity at the interface of the two fluids,...

Robert A. Van Gorder; K. V. Prasad; K. Vajravelu

2012-07-01T23:59:59.000Z

153

Experimental investigation on heat transfer characteristics of magnetic fluid flow around a fine wire under the influence of an external magnetic field  

SciTech Connect (OSTI)

Experimental investigation is conducted to get insight into convective heat transfer features of the aqueous magnetic fluid flow over a fine wire under the influence of an external magnetic field. The convective heat transfer coefficient of the aqueous magnetic fluid flow around the heated wire is measured in both the uniform magnetic field and the magnetic field gradient. The effects of the external magnetic field strength and its orientation on the thermal behaviors of the magnetic fluids are analyzed. The experimental results show that the external magnetic field is a vital factor that affects the convective heat transfer performances of the magnetic fluids and the control of heat transfer processes of a magnetic fluid flow can be possible by applying an external magnetic field. (author)

Li, Qiang; Xuan, Yimin [School of Power Engineering, Nanjing University of Science and Technology, 200 Xiao Ling Wei, Nanjing 210094 (China)

2009-04-15T23:59:59.000Z

154

Effects of turbulence model on convective heat transfer of coolant flow in a prismatic very high temperature reactor core  

SciTech Connect (OSTI)

The existing study of Spall et al. shows that only {nu}{sup 2}-f turbulence model well matches with the experimental data of Shehata and McEligot which were obtained under strongly heated gas flows. Significant over-predictions in those literatures were observed in the convective heat transfer with the other famous turbulence models such as the k-{epsilon} and k-{omega} models. In spite of such good evidence about the performance of the{nu}{sup 2}-f model, the application of the {nu}{sup 2}-f model to the thermo-fluid analysis of a prismatic core is very rare. In this paper, therefore, the convective heat transfer of the coolant flow in a prismatic core has been investigated using the {nu}{sup 2}-f model. Computational fluid dynamics (CFD) calculations have been carried out for the typical unit cell geometry of a prismatic fuel column with typical operating conditions of prismatic designs. The tested Reynolds numbers of the coolant flow are 10,000, 20,000, 30,000 and 50,000. The predicted Nusselt numbers with the {nu}{sup 2}-f model are compared with the results by the other turbulence models (k-{epsilon} and SST) as well as the empirical correlations. (authors)

Lee, S. N.; Tak, N. I.; Kim, M. H.; Noh, J. M. [Korea Atomic Energy Research Inst., Daedeok-daero 989-11, Yuseong-gu, Daejeon (Korea, Republic of)

2012-07-01T23:59:59.000Z

155

A New Heat Transfer Fluid for Concentrating Solar Systems: Particle Flow in Tubes  

Science Journals Connector (OSTI)

Abstract This paper demonstrates a new concept of heat transfer fluid (HTF) for CSP applications, developed in the frame of both a National and a European project (CSP2 FP7 project). It involves a dense suspension of small solid particles. This innovation is currently. The dense suspension of particles receiver (DSPR) consists in creating the upward circulation of a dense suspension of particles (solid fraction in the range 30%-40%) in vertical absorbing tubes submitted to concentrated solar energy. So the suspension acts as a heat transfer fluid with a heat capacity similar to a liquid HTF but only limited in temperature by the working temperature limit of the receiver tubes. Suspension temperatures up to 750 °C are expected for metallic tubes, thus opening new opportunities for high efficiency thermodynamic cycles such as supercritical steam and carbon dioxide. First experimental results were obtained during on-sun testing with CNRS solar facility of a single tube DSPR for an outlet temperature lower than 300 °C. In this lab-scale experimental setup, the solar absorber is a single opaque metallic tube, containing upward solid circulation, located inside a cylindrical cavity dug in a receiver made of refractory, and submitted to the concentrated solar radiation through a 0.10m x 0.50m slot. The absorber is a 42.4 mm o.d. stainless steel tube. SiC was used because of its thermal properties, availability and rather low cost. The 63.9 ?m particle mean diameter permits a good fluidization with almost no bubbles, for very low air velocities. Solar flux densities in the range 200-250 kW/m2 were tested resulting in solid temperature increase ranging between 50 and 150 °C. The mean wall-to-suspension heat transfer coefficient (h) was calculated from experimental data. It is very sensitive to the solid fraction of the solid suspension, which was varied from 27% to 36%. These latter values are one order of magnitude larger than the solid fraction in circulating fluidized beds operating at much higher air velocity. Heat transfer coefficients ranging from 140 to 500 W/m2.K have been obtained; i.e. 400 W/m2.K mean value for standard operating conditions at low temperature.

G. Flamant; D. Gauthier; H. Benoit; J.-L. Sans; B. Boissière; R. Ansart; M. Hemati

2014-01-01T23:59:59.000Z

156

Fluid flow and heat transfer across an elliptical hollow fiber membrane tube bank with randomly distributed features  

Science Journals Connector (OSTI)

Abstract An elliptical hollow fiber membrane tube bank (EHFMTB) has better performances while being employed for air humidification. The EHFMTB is populated in a plastic shell to form a shell-and-tube heat exchanger like membrane contactor. The tube bank is always randomly populated in practical applications because of convenience and randomness in the manufacturing process. The fluid flow and heat transfer across a randomly distributed elliptical hollow fiber membrane tube bank (REHFMTB) are investigated. To disclose the influences of the fiber arrangements on the performances, three unit cells containing 20 fibers with different randomly distributions are selected as the calculating domains. A renormalization group k–? (RNG KE) turbulence model with enhanced wall treatment is used for solving the equations governing the momentum and heat transports. The friction factor and Nusselt number across the REHFMTB under various fiber distributions, Reynolds numbers (Re), packing fractions (?) and elliptical semiaxis ratios (b/a) are numerically obtained and experimentally validated. It is found that the comprehensive heat transfer performance is deteriorated for the fluid flow across the REHFMTB.

Runhua Jiang; Minlin Yang; Sheng Chen; Si-Min Huang; Xiaoxi Yang

2014-01-01T23:59:59.000Z

157

Numerical analysis of laminar fluid flow and heat transfer in a parallel plate channel with normally in-line positioned plates  

E-Print Network [OSTI]

NUMERICAL ANALYSIS OF LAMINAR FLUID FLOW AND HEAT TRANSFER IN A PARALLEL PLATE CHANNEL WITH NORMALLY IN-LINE POSITIONED PLATES A Thesis by JOHN GRADY iVICMATH Submitted to the Office of Graduate Studies of Texas AkM University in partial... fulfillment of the requirements for the degree of MASTER OF SCIENCE December 1991 Major Subject: Mechanical Engineering NUMERICAL ANALYSIS OF LAMINAR FLUID FLOW AND HEAT TRANSFER IN A PARALLEL PLATE CHANNEI WITH NORMALLY IN-LINE POSITIONED PLATES A...

McMath, John Grady

2012-06-07T23:59:59.000Z

158

Characteristics of Fluid flow and heat transfer in Shellside of Heat Exchangers with Longitudinal Flow of Shellside Fluid with Different Supporting structures  

Science Journals Connector (OSTI)

In the paper, a simplified numerical model-the periodic unit duct model was presented for the numerical simulation of shellside characteristics in heat exchanger with longitudinal flow of shellside fluid, and its...

Yongqing Wang; Qiwu Dong; Minshan Liu

2007-01-01T23:59:59.000Z

159

Fluid flow and conjugated heat transfer in arbitrarily shaped channels via single domain formulation and integral transforms  

Science Journals Connector (OSTI)

Abstract The present work advances a recently introduced approach based on combining the Generalized Integral Transform Technique (GITT) and a single domain reformulation strategy, aimed at providing hybrid numerical–analytical solutions to convection–diffusion problems in complex physical configurations and irregular geometries. The methodology has been previously considered in the analysis of conjugated conduction–convection heat transfer problems, simultaneously modeling the heat transfer phenomena at both the fluid streams and the channels walls, by making use of coefficients represented as space variable functions with abrupt transitions occurring at the fluid–wall interfaces. The present work is aimed at extending this methodology to deal with both fluid flow and conjugated heat transfer within arbitrarily shaped channels and complex multichannel configurations, so that the solution of a cumbersome system of coupled partial differential equations defined for each individual sub-domain of the problem is avoided, with the proposition of the single-domain formulation. The reformulated problem is integral transformed through the adoption of eigenvalue problems containing the space variable coefficients, which provide the basis of the eigenfunction expansions and are responsible for recovering the transitional behavior among the different regions in the original formulation. For demonstration purposes, an application is first considered consisting of a microchannel with an irregular cross-section shape, representing a typical channel micro-fabricated through laser ablation, in which heat and fluid flow are investigated, taking into account the conjugation with the polymeric substrate. Then, a complex configuration consisting of multiple irregularly shaped channels is more closely analyzed, in order to illustrate the flexibility and robustness of the advanced hybrid approach. In both cases, the convergence behavior of the proposed expansions is presented and critical comparisons against purely numerical approaches are provided.

Diego C. Knupp; Renato M. Cotta; Carolina P. Naveira-Cotta

2014-01-01T23:59:59.000Z

160

RELAP5/MOD3 code quality assurance plan for ORNL ANS narrow channel flow and heat transfer correlations  

SciTech Connect (OSTI)

Modifications have been made to REIAP5 to account for flow and heat transfer in narrow channels between fuel plates such as found in the cores of the Advanced Neutron Source (ANS) and High Flux Isotope Reactor (HFIR) reactors. These early models were supplied by Art Ruggles of Oak Ridge National Laboratory (ORNL) and Don Fletcher of the Idaho National Engineering Laboratory (INEL) and were adapted to and implemented into RELAP5 by Rich Riemke, Rex Shumway and Ken Katsma. The purpose of this report is to document the current status of these special models in the standard version of RELAP5/MOD3 and describe the quality assurance procedures.

MIller, C.S.; Shumway, R.W.

1992-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

Thermal Storage and Advanced Heat Transfer Fluids (Fact Sheet)  

SciTech Connect (OSTI)

Fact sheet describing NREL CSP Program capabilities in the area of thermal storage and advanced heat transfer fluids: measuring thermophysical properties, measuring fluid flow and heat transfer, and simulating flow of thermal energy and fluid.

Not Available

2010-08-01T23:59:59.000Z

162

Heat transfer and heat exchangers reference handbook  

SciTech Connect (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

163

Heat Transfer and Convection Currents  

Science Journals Connector (OSTI)

...October 1965 research-article Heat Transfer and Convection Currents D. C...convection in a medium with internal heat generation is discussed semi-quantitatively...States English United Kingdom 1966 Heat transfer and convection currents Tozer D...

1965-01-01T23:59:59.000Z

164

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

E-Print Network [OSTI]

Boiling heat transfer in a hydrofoil-based micro pin fin heat sink Ali KosÃ?ar, Yoav Peles-based micro pin fin heat sink was investigated. Average two-phase heat transfer coefficients were obtained intermittent and spray-annular flows. Heat transfer coefficient trends and flow morphologies were used to infer

Peles, Yoav

165

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

E-Print Network [OSTI]

??Naphthalene sublimation and pressure measurement experiments were conducted to study heat (mass) transfer enhancement by blockages with staggered round and square holes for turbulent air… (more)

Cervantes, Joel

2012-01-01T23:59:59.000Z

166

Internal Heat Transfer Coefficient Determination in a Packed Bed From the Transient Response Due to Solid Phase Induction Heating  

E-Print Network [OSTI]

the Hydraulic Drag and Heat Transfer Coefficients in PorousT. E. W. , 1929, “Heat Transfer: A Liquid Flowing Through a5] Locke, G. L. , 1950, “Heat Transfer and Flow Friction

Geb, David; Zhou, Feng; Catton, Ivan

2012-01-01T23:59:59.000Z

167

Numerical simulation of fluid flow and heat transfer inside a rotating disk-cylinder configuration by a lattice Boltzmann model  

Science Journals Connector (OSTI)

A simple lattice Boltzmann model for numerical simulation of fluid flow and heat transfer inside a rotating disk-cylinder configuration, which is of fundamental interest and practical importance in science as well as in engineering, is proposed in this paper. Unlike existing lattice Boltzmann models for such flows, which were based on “primitive-variable” Navier-Stokes equations, the target macroscopic equations of the present model for the flow field are vorticity–stream function equations, inspired by our recent work designed for nonrotating flows [S. Chen, J. Tölke, and M. Krafczyk, Phys. Rev. E 79, 016704 (2009); S. Chen, J. Tölke, S. Geller, and M. Krafczyk, Phys. Rev. E 78, 046703 (2008)]. The flow field and the temperature field both are solved by the D2Q5 model. Compared with the previous models, the present model is more efficient, more stable, and much simpler. It was found that, even though with a relatively low grid resolution, the present model can still work well when the Grashof number is very high. The advantages of the present model are validated by numerical experiments.

Sheng Chen; Jonas Tölke; Manfred Krafczyk

2009-07-14T23:59:59.000Z

168

6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi'an, China, 11-15 July 2009  

E-Print Network [OSTI]

6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi in pipeline transportation, where it is important to identify and control bottlenecks influence on production be viewed as the hydrodynamic equivalent of the Mach number for gas flows. Simplified hydraulic theories

Al Hanbali, Ahmad

169

Numerical Investigation on the Heat Transfer Enhancement Using Micro/Nano Phase-Change Particulate Flow.  

E-Print Network [OSTI]

??The introduction of phase change material fluid and nanofluid in micro-channel heat sink design can significantly increase the cooling capacity of the heat sink because… (more)

Xing, Keqiang

2007-01-01T23:59:59.000Z

170

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

171

3-D Numerical Simulation of Heat Transfer and Turbulent Flow in a Receiver Tube of Solar Parabolic Trough Concentrator with Louvered Twisted-tape Inserts  

Science Journals Connector (OSTI)

Abstract High temperature and higher-thermal efficiency for CSP cycles are main goals to improve trough collector's technologies. For a parabolic trough collector the major factor for optimum heat transfer from sun to the heat transfer fluid passing in the absorber tube is to have high convection heat transfer coefficient. Literature shows that absorber tubes with various tape inserts are used and recommended to produce high convection coefficient. Typical twisted-tape (TT) enhances heat exchange between tube surface and working fluid by generating turbulent swirling flow. In this study, enhancement of convection coefficient in the receiver tube of a solar parabolic trough concentrator that the absorber tube is equipped with a new perforated louvered twisted- tape (LTT) is studied numerically. For numerical simulations three different twist ratios (TR), TR=y/W= 2.67, 4, 5.33 (y is the length required for one twist and W is the width of the tape) are used in an experimental laboratory trough collector. Flow is assumed turbulent due to louvered perforated surface and rotational shape of the tape. For thermal boundary condition, non- uniform wall solar heat flux is determined by Soltrace code on the outer surface of the absorber tube. Heat transfer rate and pressure drop are determined for fully developed condition for several Reynolds numbers based on the tube diameter and flow mean velocity. Results show that the heat transfer coefficient and pressure drop increase significantly in comparison with a typical plain twisted-tape in the tube and a plain tube.

Sh. Ghadirijafarbeigloo; A.H. Zamzamian; M. Yaghoubi

2014-01-01T23:59:59.000Z

172

Numerical Evaluation of Flow and Heat Transfer in Plate-Pin Fin Heat Sinks with Various Pin Cross-Sections  

E-Print Network [OSTI]

in Table 3. The grid systems for all heat sink models areregion. The grid system for one of the heat sinks is shown

Zhou, Feng; Catton, Ivan

2011-01-01T23:59:59.000Z

173

Heat transfer effectiveness of three-fluid separated heat pipe exchanger  

Science Journals Connector (OSTI)

A heat transfer model for three-fluid separated heat pipe exchanger was analyzed, and the temperature transfer matrix for general three-fluid separated heat exchanger working in parallel-flow or counter- ... It w...

Chengming Shi; Yang Wang; Ying Yang; Quan Liao

2011-02-01T23:59:59.000Z

174

3D numerical simulation on fluid flow and heat transfer characteristics in multistage heat exchanger with slit fins  

Science Journals Connector (OSTI)

In this paper, a numerical investigation is performed for three-stage heat exchangers with plain plate fins and slit ... are arranged in a staggered way, and heat conduction in fins is considered. In order ... av...

W. Q. Tao; Y. P. Cheng; T. S. Lee

2007-11-01T23:59:59.000Z

175

Faculty Positions Heat Transfer and  

E-Print Network [OSTI]

Faculty Positions Heat Transfer and Thermal/Energy Sciences Naval Postgraduate School Monterey-track faculty position at the assistant professor level in the areas of Heat Transfer and Thermal/Fluid Sciences

176

FINITE ELEMENT METHOD IN FLUID MECHANICS & HEAT TRANSFER  

E-Print Network [OSTI]

FINITE ELEMENT METHOD IN FLUID MECHANICS & HEAT TRANSFER AERSP-560 Department : Aerospace element techniques to especially fluid flow and heat transfer problems. A student who successfully method and write full sized application codes for analyzing fluid flow and heat transfer problems

Camci, Cengiz

177

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

178

Pulsatile flow and heat transfer of a magneto-micropolar fluid through a stenosed artery under the influence of body acceleration  

E-Print Network [OSTI]

With an aim to investigate the effect of externally imposed body acceleration and magnetic field on pulsatile flow of blood through an arterial segment having stenosis is under consideration in this paper. The flow of blood is presented by a unsteady micropolar fluid and the heat transfer characteristics have been taken into account. The non-linear equations that governing the flow are solved numerically using finite difference technique by employing a suitable coordinate transformation. The numerical results have been observed for axial and microrotation component of velocity, fluid acceleration, wall shear stress(WSS), flow resistance, temperature and the volumetric flow rate. It thus turns out that the rate of heat transfer increases with the increase of Hartmann number $H$, while the wall shear stress has a reducing effect on the Hartmann number $H$ and an enhancing effect on microrotation parameter $K$ as well as the constriction height $\\delta$.

Shit, G C

2012-01-01T23:59:59.000Z

179

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 forsimulation of heat and moisture transfer in a human-

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

2009-01-01T23:59:59.000Z

180

Heat transfer and fluid flow over a single disk in a fluid rotating as a rigid body  

Science Journals Connector (OSTI)

Laminar heat transfer problem is analyzed for a disk rotating ... the angular speed ? in a co-rotating fluid (with the angular speed ?). The fluid is swirled in accordance with a forced- ... self-similar profiles...

Igor V. Shevchuk Ph.D.; Matthias H. Buschmann

2004-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

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 schemes proposed by Yan and Lin (1999b) for modeling the heat transfer coefficient in both a single- phase

Kandlikar, Satish

182

Unsteady hydromagnetic free-convection flow with radiative heat transfer in a rotating fluid  

Science Journals Connector (OSTI)

We study the unsteady free-convection flow near a moving infinite flat plate in a totating medium by imposing a time-dependent perturbation on a constant plate temperature. The temperatures involved are assume...

A. R. Bestman; S. K. Adjepong

183

6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi'an, China, 11-15 July 2009  

E-Print Network [OSTI]

6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion Xi, hydrogen fuel, obtained from ethanol, is a potentially strong contender as an energy carrier based for more secure and cleaner energy carrier (Barreto, Makihira, and Riahi 2003). Hydrogen can be produced

Khandekar, Sameer

184

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

SciTech Connect (OSTI)

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

Kumar Sridharan; Mark Anderson; Todd Allen; Michael Corradini

2012-01-30T23:59:59.000Z

185

NEWTON: Greenhouse Gas and Heat Transfer  

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

186

Heat transfer and friction factor of water based TiO2 and SiO2 nanofluids under turbulent flow in a tube  

Science Journals Connector (OSTI)

Abstract The heat transfer coefficient and friction factor of TiO2 and SiO2 water based nanofluids flowing in a circular tube under turbulent flow are investigated experimentally under constant heat flux boundary condition. TiO2 and SiO2 nanofluids with an average particle size of 50 nm and 22 nm respectively are used in the working fluid for volume concentrations up to 3.0%. Experiments are conducted at a bulk temperature of 30 °C in the turbulent Reynolds number range of 5000 to 25,000. The enhancements in viscosity and thermal conductivity of TiO2 are greater than SiO2 nanofluid. However, a maximum enhancement of 26% in heat transfer coefficients is obtained with TiO2 nanofluid at 1.0% concentration, while SiO2 nanofluid gave 33% enhancement at 3.0% concentration. The heat transfer coefficients are lower at all other concentrations. The particle concentration at which the nanofluids give maximum heat transfer has been determined and validated with property enhancement ratio. It is observed that the pressure drop is directly proportional to the density of the nanoparticle.

W.H. Azmi; K.V. Sharma; P.K. Sarma; Rizalman Mamat; G. Najafi

2014-01-01T23:59:59.000Z

187

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

E-Print Network [OSTI]

? Specific Resistance?s 2/m6? Diameter?mm? Specific Resistance?s 2/m6? Diameter?mm? Specific Resistance?s 2/m6? 10 77392033.96 125 118.87 400 0.249907 15 9024280.53 150 45.23 450 0.133866 20 1964433.28 175 19.98 500 0.076587 25 602024... pipe and the old cast iron pipe. It is 0.30 0.021 z d? = (6) (1.2/um> )s Defined the ratio of flow resistance of mediate water and sewage is zHw, the ratio of the flux is wz,and the ratio of velocity is z wUr u u= , supposed the inside...

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

2006-01-01T23:59:59.000Z

188

THE INFLUENCE OF REPOSITORY THERMAL LOAD ON MULTIPHASE FLOW AND HEAT TRANSFER IN THE UNSATURATED ZONE OF YUCCA MOUNTAIN  

SciTech Connect (OSTI)

This paper investigates the impact of proposed repository thermal-loading on mountain-scale flow and heat transfer in the unsaturated fractured rock of Yucca Mountain, Nevada. In this context, a model has been developed to study the coupled thermal-hydrological (TH) processes at the scale of the entire Yucca Mountain. This mountain-scale TH model implements the current geological framework and hydrogeological conceptual models, and incorporates the latest rock thermal and hydrological properties. The TH model consists of a two-dimensional north-south vertical cross section across the entire unsaturated zone model domain and uses refined meshes near and around the proposed repository block, based on the current repository design, drift layout, thermal loading scenario, and estimated current and future climatic conditions. The model simulations provide insights into thermally affected liquid saturation, gas- and liquid-phase fluxes, and elevated water and rock temperature, which in turn allow modelers to predict the changes in water flux driven by evaporation/condensation processes, and drainage between drifts.

Yu-Shu Wu, Sumit Mukhopadhyay, Keni Zhang, and G. S. Bodvarsson

2006-04-16T23:59:59.000Z

189

Frame Heat Transfer Research  

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

190

Proceedings of NHTC'00: 34 th National Heat Transfer Conference  

E-Print Network [OSTI]

Proceedings of NHTC'00: 34 th National Heat Transfer Conference Pittsburgh, Pennsylvania, August 20 ON SINGLE- AND TWO-PHASE HEAT TRANSFER CHARACTERISTICS IN A MICROCHANNEL Michael S June Graduate Student study investigates the heat transfer characteristics of single and two-phase flows in a 200 m wide

Kandlikar, Satish

191

Heat and mass transfer of a viscous heat generating fluid with Hall currents  

Science Journals Connector (OSTI)

A study of natural convection in hydrodynamic flows of a viscous heat generating fluid in the presence of Hall currents and ... out. The governing equations for the magnetohydrodynamic fluid flow and heat transfer

P. C. Ram; S. S. Singh; R. K. Jain

192

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

E-Print Network [OSTI]

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

Thole, Karen A.

193

Analysis of three-dimensional heat transfer in micro-channel heat sinks  

E-Print Network [OSTI]

, the three-dimensional fluid flow and heat transfer in a rectangular micro-channel heat sink are ana- lyzedAnalysis of three-dimensional heat transfer in micro-channel heat sinks Weilin Qu, Issam Mudawar numerically using water as the cooling fluid. The heat sink consists of a 1-cm2 silicon wafer. The micro

Qu, Weilin

194

Reply to “Comment on ‘Heat transfer and fluid flow in microchannels and nanochannels at high Knudsen number using thermal lattice-Boltzmann method”’  

Science Journals Connector (OSTI)

In this reply to the Comment by Li-Shi Luo, we discuss the results of the lattice Bhatnagar-Gross-Krook (LBGK) model for high-Knudsen-number (Kn) flow and heat transfer, in the range of Kn?1. We present various studies employing the LBGK model for high-Kn flow and heat transfer simulations. It is concluded that, with the use of the LBGK model in the thermal lattice Boltzmann method for Kn?0.8, some approximations appear in the negative pressure deviation from the linear distribution along the channel. But for Kn<0.8, the velocity and temperature profiles, compressibility effects, Knudsen layer capturing, and Knudsen paradox phenomenon can be predicted by the LBGK model. We also reject Li-Shi Luo’s claim about the nonconvergence of our numerical scheme by presenting a velocity profile across the channel corresponding to three different high-resolution meshes.

J. Ghazanfarian and A. Abbassi

2011-10-25T23:59:59.000Z

195

Spring 2014 Heat Transfer -2  

E-Print Network [OSTI]

Spring 2014 Heat Transfer - 2 A thin electronic chip is in the shape of a square wafer, b = 1 cm surface of the chip with a heat transfer coefficient of h = 100 W/m2 -K. Assume the chip has a uniform per side with a mass of m = 0.3 grams and specific heat of C = 103 J/kg-K. The chip is mounted

Virginia Tech

196

Spring 2014 Heat Transfer -1  

E-Print Network [OSTI]

Spring 2014 1 Heat Transfer - 1 Consider a cylindrical nuclear fuel rod of length L and diameter df and the tube at a rate m , and the outer surface of the tube is well insulated. Heat generation occurs within. The specific heat of water pc , and the thermal conductivity of the fuel rod fk are constants. The system

Virginia Tech

197

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]

1980. Numerical heat transfer and fluid flow. Washington,of heat transfer by natural convection across vertical fluidFluid Dynamics and Conduction Simulations of Heat Transfer

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

2003-01-01T23:59:59.000Z

198

Influences of peripherally-cut twisted tape insert on heat transfer and thermal performance characteristics in laminar and turbulent tube flows  

SciTech Connect (OSTI)

Effects of peripherally-cut twisted tape insert on heat transfer, friction loss and thermal performance factor characteristics in a round tube were investigated. Nine different peripherally-cut twisted tapes with constant twist ratio (y/W = 3.0) and different three tape depth ratios (DR = d/W = 0.11, 0.22 and 0.33), each with three different tape width ratios (WR = w/W = 0.11, 0.22 and 0.33) were tested. Besides, one typical twisted tape was also tested for comparison. The measurement of heat transfer rate was conducted under uniform heat flux condition while that of friction factor was performed under isothermal condition. Tests were performed with Reynolds number in a range from 1000 to 20,000, using water as a working fluid. The experimental results revealed that both heat transfer rate and friction factor in the tube equipped with the peripherally-cut twisted tapes were significantly higher than those in the tube fitted with the typical twisted tape and plain tube, especially in the laminar flow regime. The higher turbulence intensity of fluid in the vicinity of the tube wall generated by the peripherally-cut twisted tape compared to that induced by the typical twisted tape is referred as the main reason for achieved results. The obtained results also demonstrated that as the depth ratio increased and width ratio decreased, the heat transfer enhancement increased. Over the range investigated, the peripherally-cut twisted tape enhanced heat transfer rates in term of Nusselt numbers up to 2.6 times (turbulent regime) and 12.8 times (laminar regime) of that in the plain tube. These corresponded to the maximum performance factors of 1.29 (turbulent regime) and 4.88 (laminar regime). (author)

Eiamsa-ard, Smith [Department of Mechanical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Seemawute, Panida [Department of Civil Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand); Wongcharee, Khwanchit [Department of Chemical Engineering, Faculty of Engineering, Mahanakorn University of Technology, Bangkok 10530 (Thailand)

2010-09-15T23:59:59.000Z

199

Development and adaptation of conduction and radiation heat-transfer computer codes for the CFTL. [Core Flow Test Loop; RODCON; HOTTEL  

SciTech Connect (OSTI)

RODCON and HOTTEL are two computational methods used to calculate thermal and radiation heat transfer for the Core Flow Test Loop (CFTL) analysis efforts. RODCON was developed at ORNL to calculate the internal temperature distribution of the fuel rod simulator (FRS) for the CFTL. RODCON solves the time-dependent heat transfer equation in two-dimensional (R angle) cylindrical coordinates at an axial plane with user-specified radial material zones and time- and position-variant surface conditions at the FRS periphery. Symmetry of the FRS periphery boundary conditions is not necessary. The governing elliptic, partial differential heat equation is cast into a fully implicit, finite-difference form by approximating the derivatives with a forward-differencing scheme with variable mesh spacing. The heat conduction path is circumferentially complete, and the potential mathematical problem at the rod center can be effectively ignored. HOTTEL is a revision of an algorithm developed by C.B. Baxi at the General Atomic Company (GAC) to be used in calculating radiation heat transfer in a rod bundle enclosed in a hexagonal duct. HOTTEL uses geometric view factors, surface emissivities, and surface areas to calculate the gray-body or composite view factors in an enclosure having multiple reflections in a nonparticipating medium.

Conklin, J.C.

1981-08-01T23:59:59.000Z

200

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 forCheng, X. -Y. 2005. Heat and moisture transfer with sorption

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

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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 from a Rotating Disk  

Science Journals Connector (OSTI)

...August 1956 research-article Heat Transfer from a Rotating Disk E. C. Cobb...little has been published on the heat transfer. For laminar conditions theoretical...experimental investigation of the heat transfer for a range of conditions from...

1956-01-01T23:59:59.000Z

202

Heat and moisture transfer through clothing  

E-Print Network [OSTI]

Mathematical simulation of heat and moisture transfer in aand R. C. Eberhart (ed), Heat transfer in medicine andFan, J. 2008. Study of heat and moisture transfer within

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

2009-01-01T23:59:59.000Z

203

Numerical analysis of the scavenge flow and convective heat transfer in large two-stroke marine diesel engines  

Science Journals Connector (OSTI)

Abstract A novel computational fluid dynamics (CFD) model is presented for the study of the scavenging process and convective heat transfer in a large two-stroke low-speed uniflow-scavenged marine diesel engine. The engine is modeled using a fully resolved 12° sector, corresponding to one scavenge port, with cyclic boundaries in the tangential direction. The CFD model is strongly coupled to experiments and effectively provides a high order “interpolation” of the engine processes through the solution of the Reynolds-Averaged Navier–Stokes (RANS) equations subject to boundary conditions obtained through experiments. The imposed experimental data includes time histories of the pressure difference across the engine and the heat release during combustion. The model is validated by a numerical sensitivity analysis and through a comparison of model predictions and experimental data, which shows a good agreement. The results show an effective scavenging and a low convective heat loss in agreement with experimental data for large marine diesel engines.

E. Sigurdsson; K.M. Ingvorsen; M.V. Jensen; S. Mayer; S. Matlok; J.H. Walther

2014-01-01T23:59:59.000Z

204

ASME Journal of Heat Transfer Vol.118, pp.592-598, 1996  

E-Print Network [OSTI]

. The coupled governing equations for time- dependent convective heat transfer in the fluid flow and conduction to pay increasing attention to the study of heat transfer and fluid flow characteristicsASME Journal of Heat Transfer Vol.118, pp.592-598, 1996 OSCILLATORY HEAT TRANSFER IN A PIPE

Zhao, Tianshou

205

Heat transfer in microsphere insulation  

Science Journals Connector (OSTI)

The results of an investigation of heat transfer in a new type of insulation (microsphere insulation) are presented. The effects of the ... gas pressure on the thermal conductivity of the insulation were investig...

R. Wawryk; J. Rafa?owicz

206

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 uniform electric field in the vicinity of the condensation surface the extraction of liquid...

Wawzyniak, Markus

2012-06-07T23:59:59.000Z

207

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

208

Heat Transfer Fluids Containing Nanoparticles | Argonne National...  

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

Heat Transfer Fluids Containing Nanoparticles Technology available for licensing: A stable, nonreactive nanofluid that exhibits enhanced heat transfer properties with only a...

209

Numerical predictions on fluid flow and heat transfer in U-shaped channel with the combination of ribs, dimples and protrusions under rotational effects  

Science Journals Connector (OSTI)

Abstract Recently, dimple and protrusion structure has been proved as an effective heat transfer augmentation approach on coolant channel due to its advantage on pressure penalty. A compound heat transfer enhancement technique, the combination of ribs, dimples or protrusions, is applied to a U-shaped square channel similar with the gas turbine blade internal passage. Considering the rotational condition of gas turbine blade on operation, the effect of rotation is also investigated for the coolant channel in order to approximate more to the real operation condition. Thus, the objective of this study is to discuss the effect of rotation on fluid flow and heat transfer performance of turbine blade similar U-shaped channel with the combination structure of ribs, dimples or protrusions. The investigated Reynolds number is 1.25 million and considered rotational number includes 0, 0.4 and 0.6. From the results, the fluid patterns of two-pass channel with compound heat transfer enhancement structure are presented for none-rotating and rotating cases. Meanwhile, spatially Nusselt distributions of roughened walls are obtained to reveal the heat transfer rates. Finally, the area averaged Nusselt number ratio and channel friction penalty are evaluated. The results indicate that rib-protrusion structure seems to be the most effective structure while rib-dimple structure has only slight advantage than ribbed channel. Furthermore, the additional friction penalty by dimple and protrusion structure is tiny. It can also be expected that, the thermal performance of this compound structure can be even improved after a denser arrangement of dimple/protrusion structure and optimal shape design.

Zhongyang Shen; Yonghui Xie; Di Zhang

2015-01-01T23:59:59.000Z

210

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

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

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

211

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

SciTech Connect (OSTI)

A multidimensional, mountain-scale, thermal-hydrologic (TH) numerical model is presented for investigating unsaturated flow behavior in response to decay heat from the radioactive waste repository in the Yucca Mountain unsaturated zone (UZ), Nevada. The model, consisting of both two-dimensional (2-D) and three-dimensional (3-D) representations of the UZ repository system, is based on the current repository design, drift layout, thermal loading scenario, and estimated current and future climate conditions. This mountain-scale TH model evaluates the coupled TH processes related to mountain-scale UZ flow. It also simulates the impact of radioactive waste heat release on the natural hydrogeological system, including heat-driven processes occurring near and far away from the emplacement tunnels or drifts. The model simulations predict thermally perturbed liquid saturation, gas- and liquid-phase fluxes, and water and rock temperature elevations, as well as the changes in water flux driven by evaporation/condensation processes and drainage between drifts. These simulations provide mountain-scale thermally perturbed flow fields for assessing the repository performance under thermal loading conditions.

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

2005-05-25T23:59:59.000Z

212

Convective heat flow probe  

DOE Patents [OSTI]

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

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

1984-01-09T23:59:59.000Z

213

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

E-Print Network [OSTI]

: : : : : : : : : : : : : : : : : : : : : : : : 15 VI RESULTS AND DISCUSSION : : : : : : : : : : : : : : : : : : : 17 A. Effect of Reynolds Number ReDh . . . . . . . . . . . . . . 17 B. Effect of Height of Pins, H=D . . . . . . . . . . . . . . . . 21 C. Effect of Stream Wise Spacing of Pins, SL=D... Pressure Drop for D = 2:54cm : 23 9 Effect of H=D on Thermal Performance for D = 2:54cm : : : : : : : 24 10 Effect of SL=D on Heat Transfer Enhancement for D=1.27cm : : : : 25 11 Effect of SL=D on Increase of Overall Pressure Drop for D = 1:27cm 26 12...

Achanta, Vamsee Satish

2004-09-30T23:59:59.000Z

214

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 exit direction on various target surface heat transfer distributions. A two-channel test section...

Huang, Yizhe

2012-06-07T23:59:59.000Z

215

Planetary heat flow measurements  

Science Journals Connector (OSTI)

...ESA's Rosetta mission towards comet Churyumov-Gerasimenko. It...Heat flow measurements on comets have a different motivation...penetrator is by no means limited to comets; it has also been tested in...measurement. Currently, a landing on Mercury within the framework...

2005-01-01T23:59:59.000Z

216

Convective heat transfer in the nonstationary motion of a Maxwellian fluid between parallel planes  

Science Journals Connector (OSTI)

The convective heat-transfer problem is investigated for a Maxwellian fluid in generalized Couette flow in the case...

Z. P. Shul'man; É. A. Zal'tsgendler

1970-06-01T23:59:59.000Z

217

HEAT AND MOISTURE TRANSFER THROUGH CLOTHING  

E-Print Network [OSTI]

J. & Cheng, X. -Y. 2005. Heat and moisture transfer withof the combined diffusion of heat and water vapor throughMathematical simulation of heat and moisture transfer in a

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

2009-01-01T23:59:59.000Z

218

Characterization of the effect of Froude number on surface waves and heat transfer in inclined turbulent  

E-Print Network [OSTI]

Characterization of the effect of Froude number on surface waves and heat transfer in inclined describes wave/heat transfer phenomena in inclined turbulent open surface water flows. The experiments were. These changes lead to a heat transfer improvement, enough to double the heat transfer coefficient

Abdou, Mohamed

219

1 Copyright 2013 by ASME Proceedings of the ASME 2013 Summer Heat Transfer Conference  

E-Print Network [OSTI]

the misting process, the fluid flow and heat transfer of humid air as well as the heat transfer across and heat transfer in both fluid and solid domains. As an example, Aroussi .et al [2] numerically simulated1 Copyright © 2013 by ASME Proceedings of the ASME 2013 Summer Heat Transfer Conference HT2013 July

Bahrami, Majid

220

Heat Transfer Measurements for a Horizontal Micro-Tube Using Liquid Crystal Thermography  

E-Print Network [OSTI]

62 TC02-007 Heat Transfer Measurements for a Horizontal Micro-Tube Using Liquid Crystal-tube and 1000m micro-tube. In the single-phase heat transfer experiments, the fully-developed flow heat transfer were also measured using thermocouples (TC). The results showed that the heat transfer coefficient

Ghajar, Afshin J.

Note: This page contains sample records for the topic "flow heat transfer" 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

Comment on “Heat transfer and fluid flow in microchannels and nanochannels at high Knudsen number using thermal lattice-Boltzmann method”  

Science Journals Connector (OSTI)

In this Comment we reveal the falsehood of the claim that the lattice Bhatnagar-Gross-Krook (BGK) model “is capable of modeling shear-driven, pressure-driven, and mixed shear-pressure-driven rarified [sic] flows and heat transfer up to Kn=1 in the transitional regime” made in a recent paper [Ghazanfarian and Abbassi, Phys. Rev. E 82, 026307 (2010)]. In particular, we demonstrate that the so-called “Knudsen effects” described are merely numerical artifacts of the lattice BGK model and they are unphysical. Specifically, we show that the erroneous results for the pressure-driven flow in a microchannel imply the false and unphysical condition that 6?Kn

Li-Shi Luo

2011-10-25T23:59:59.000Z

222

Heat transfer studies, quarterly report  

SciTech Connect (OSTI)

Drying in subresidually-saturated systems at elevated temperatures has been studied for two different operating conditions. One condition started with flowing nitrogen gas through the test section and simultaneously heating up the porous medium at the same time (denoted in what follows as the ``transient heating case``). The other condition started initially with heating up the porous medium with no flow, and then running the nitrogen gas flow through the test section after a steady-state temperature distribution had been reached (denoted in what follows as the ``steady heating case``). A 90{degrees}C isothermal boundary condition was set on the aluminum wall. An average of 9% discrepancy in the mass balance calculation compared to the digital balance measurement has been found in the transient heating case. An average of 4.3% discrepancy in the mass balance calculation compared to the digital balance measurement has been found after the nitrogen gas flowed through test section for the steady heating case. A large discrepancy has also been found before the nitrogen gas admitted to the test section. This is because some of subresidual water in the test section has been drained out from the bottom due to the gravity effect and the strong convection flow in the porous medium before the nitrogen gas is admitted. This discrepancy may be reduced by closing the end tube at bottom before the nitrogen gas is admitted to the test section. The drying characteristics of this system are reported. A theoretical study has also been initiated in an attempt to supplement the experimental results, and this system is described in the report. A one-dimensional transient system is assumed in which a two-component (condensable and noncondensable) gas mixture flows through a porous medium with evaporation. The numerical calculation will be performed in the future work to compare to the experimental results.

Boehm, R.; Chen, Y.T.; Sathappan, A.K.

1996-01-19T23:59:59.000Z

223

Convective heat transfer on leeward building walls in an urban environment: Measurements in an outdoor scale model  

E-Print Network [OSTI]

surface, Proc. 5 th Int. Heat Transfer Conf. 3 (1974) 129-a vertical plate, J. Heat Transfer 109(1) [13] K. Patel,Experimental study of heat transfer in turbulent flows over

Nottrott, A.; Onomura, S.; Inagaki, A.; Kanda, M.; Kleissl, J.

2011-01-01T23:59:59.000Z

224

ASME Journal of Heat Transfer Vol. 121(3), pp.646-652, 1999  

E-Print Network [OSTI]

#12;3 Introduction Buoyancy-induced convective fluid flow with and without phase change heat transfer1 ASME Journal of Heat Transfer Vol. 121(3), pp.646-652, 1999 Variations of Buoyancy-Induced Mass-change heat transfer in a vertical porous tube heated at a constant heat flux. Experiments were carried out

Zhao, Tianshou

225

An experimental investigation of turbine blade heat transfer and turbine blade trailing edge cooling  

E-Print Network [OSTI]

studies have investigated the fluid flow and heat transfer behavior in high Reynolds number flows. Blair [7,8] investigated the effect of grid generated turbulence on flat plate heat transfer. He showed that turbulent heat transfer coefficient in flow... AN EXPERIMENTAL INVESTIGATION OF TURBINE BLADE HEAT TRANSFER AND TURBINE BLADE TRAILING EDGE COOLING A Dissertation by JUNGHO CHOI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment...

Choi, Jungho

2005-02-17T23:59:59.000Z

226

Journal of Heat Transfer1999 JHT Heat Transfer Gallery Department of Mechanical 8. Aerospace Engineering  

E-Print Network [OSTI]

Journal of Heat Transfer1999 JHT Heat Transfer Gallery S. M. You Department of Mechanical 8 Transfer Visualization Committee organized two photo gallery sessions in 1998. The International Heat Transfer Photo Gallery was held at the l la' International Heat Transfer Conference (IHTC) in Kyongju

Kihm, IconKenneth David

227

Modelling of Heat Transfer in Single Crystal Growth  

E-Print Network [OSTI]

An attempt is made to review the heat transfer and the related problems encountered in the simulation of single crystal growth. The peculiarities of conductive, convective and radiative heat transfer in the different melt, solution, and vapour growth methods are discussed. The importance of the adequate description of the optical crystal properties (semitransparency, specular reflecting surfaces) and their effect on the heat transfer is stresses. Treatment of the unknown phase boundary fluid/crystal as well as problems related to the assessment of the quality of the grown crystals (composition, thermal stresses, point defects, disclocations etc.) and their coupling to the heat transfer/fluid flow problems is considered. Differences between the crystal growth simulation codes intended for the research and for the industrial applications are indicated. The problems of the code verification and validation are discussed; a brief review of the experimental techniques for the study of heat transfer and flow structu...

Zhmakin, Alexander I

2014-01-01T23:59:59.000Z

228

Heat Transfer through Strongly Magnetized Ferrofluids  

Science Journals Connector (OSTI)

8 April 1991 research-article Heat Transfer through Strongly Magnetized Ferrofluids P. J. Blennerhassett...under microgravity conditions, the ratio of the steady heat transfer by convection to that by conduction can be up to 10...

1991-01-01T23:59:59.000Z

229

Experimental study on heat transfer characteristics of internal heat exchangers for CO2 system under cooling condition  

Science Journals Connector (OSTI)

This paper presents the heat transfer characteristics of the internal heat exchanger (IHX) for CO2 heat pump system. The influence on the IHX length, the mass flow rate, the shape of IHX, the operating condition,...

Young Chul Kwon; Dae Hoon Kim; Jae Heon Lee…

2009-03-01T23:59:59.000Z

230

MHD EFFECTS ON HEAT TRANSFER IN A MOLTEN SALT BLANKET Sergey Smolentsev, Reza Miraghaie, Mohamed Abdou  

E-Print Network [OSTI]

MHD EFFECTS ON HEAT TRANSFER IN A MOLTEN SALT BLANKET Sergey Smolentsev, Reza Miraghaie, Mohamed-mail (Sergey Smolentsev): Sergey@fusion.ucla.edu Heat transfer in closed channel flows of molten salts (MS of the concept is that the flows in the FW channels are turbulent to provide a high heat transfer coefficient

Abdou, Mohamed

231

Heat Transfer Engineering, 28(6):525540, 2007 Copyright C Taylor and Francis Group, LLC  

E-Print Network [OSTI]

Heat Transfer Engineering, 28(6):525­540, 2007 Copyright C Taylor and Francis Group, LLC ISSN: 0145-7632 print / 1521-0537 online DOI: 10.1080/01457630701193906 Heat Transfer Measurements, Flow Pattern Maps, Stillwater, Oklahoma, USA Local heat transfer coefficients and flow parameters were measured for air

Ghajar, Afshin J.

232

Heat Transfer at Small Grashof Numbers  

Science Journals Connector (OSTI)

...January 1957 research-article Heat Transfer at Small Grashof Numbers J. J...physical arguments suggest that the heat transfer from a body, immersed in a fluid...the problem is small. However, heat-transfer rates predicted in this fashion...

1957-01-01T23:59:59.000Z

233

ME 519: THEORY OF HEAT TRANSFER Instructor  

E-Print Network [OSTI]

ME 519: THEORY OF HEAT TRANSFER Fall 2014 Instructor: Class time: Classroom: Office Hours: Prof Tuesday 4­5pm or by appointment Class description This course will cover the fundamentals of heat transfer. An introductory course in heat transfer (ME 419 or equivalent) is pre-requisite. Grading 20% Homework 25% Exam 1

Lin, Xi

234

Radiative Heat Transfer in Enhanced Hydrogen Outgassing of Glass  

E-Print Network [OSTI]

Kaviany and B.P. Singh, “Radiative heat transfer in porousmedia”, Advances in Heat Transfer, vol. 23, no. 23, pp. 133–Thermal radiation heat transfer, Hemisphere Publishing Co. ,

Kitamura, Rei; Pilon, Laurent

2009-01-01T23:59:59.000Z

235

M. Bahrami ENSC 388 (F09) Forced Convection Heat Transfer 1 Forced Convection Heat Transfer  

E-Print Network [OSTI]

1 Forced Convection Heat Transfer Convection is the mechanism of heat transfer through a fluid / The convective heat transfer coefficient h strongly depends on the fluid properties and roughness of the solid. As a result, the heat transfer from the solid surface to the fluid layer adjacent to the surface

Bahrami, Majid

236

Heat Transfer Research, 2010, Vol. 41, No. 6 Turbine Aero-Heat Transfer Studies  

E-Print Network [OSTI]

AU TH O R PR O O F Heat Transfer Research, 2010, Vol. 41, No. 6 Turbine Aero-Heat Transfer Studies in Rotating Research Facilities CENGIZ CAMCI Turbomachinery Aero-Heat Transfer Laboratory, Department The present paper deals with the experimental aero-heat transfer studies performed in rotating turbine

Camci, Cengiz

237

FEHM (Finite Element Heat and Mass Transfer Code)  

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

238

Heat transfer through a water spray curtain under the effect of a strong radiative source  

E-Print Network [OSTI]

Heat transfer through a water spray curtain under the effect of a strong radiative source P. Boulet - mail Pascal.Boulet@lemta.uhp-nancy.fr Keywords : heat transfer, radiative transfer, vaporization, convection, water spray Abstract Heat transfer inside a participating medium, made of droplets flowing in gas

Paris-Sud XI, Université de

239

Conjugated heat transfer in the flow of a non-Newtonian fluid with variable properties in a flat duct  

Science Journals Connector (OSTI)

We solve the problem of the flow of a nonlinearly viscoelastic fluid in the presence of large pressure drops and appreciable nonisothermicity.

N. V. Tyabin; O. Kh. Dakhin; A. V. Baranov…

1983-09-01T23:59:59.000Z

240

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

E-Print Network [OSTI]

Flow calculations for Yucca Mountain groundwater travelunsaturated model of Yucca Mountain, Nevada, Journal ofinto drifts at Yucca Mountain, Journal of Contaminant

Birkholzer, Jens T.; Zhang, Yingqi

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

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

E-Print Network [OSTI]

surfaces. Similar experiments were also performed on a pure copper surface. In addition, experiments were performed using compact condensers. Micro-scale patterns fabricated on the refrigerant side of the compact heat exchanger were observed to cause...

Jeon, Sae Il

2012-10-19T23:59:59.000Z

242

Earth's Crust: Heat Flow Relationships  

Science Journals Connector (OSTI)

... of heat flow through the Earth's surface at any point requires two measurements, the geothermal gradient itself and the thermal conductivity of the adjacent rocks. In the oceanic crust, ... variations in heat flow from point to point are governed essentially by variations in the geothermal gradient. In continents, however, the story is different. Correlation and regression analyses carried ...

Our Geomagnetism Correspondent

1970-07-11T23:59:59.000Z

243

Constructal multi-scale package of vertical channels with natural convection and maximal heat transfer density. CONSTRUCTAL DESIGN: THE GENERATION OF MULTI-SCALE HEAT  

E-Print Network [OSTI]

transfer density. CONSTRUCTAL DESIGN: THE GENERATION OF MULTI-SCALE HEAT AND FLUID FLOW STRUCTURES-scale structures in natural convection with the objective of maximizing the heat transfer density, or the heat transfer rate per unit of volume§ . The flow volume is filled with vertical equidistant heated blades

Kihm, IconKenneth David

244

Dt2boool2> Nora Heat Transfer Correlations  

E-Print Network [OSTI]

Dt2boool2> Nora Heat Transfer Correlations in Nuclear Reactor Safety Calculations VW CORRELATIONS IN NUCLEAR REACTOR SAFETY CALCULATIONS SAK-5 H. Abel-Larsen, Ris� A. J. T. J. A. K. Olsen.1. Critical heat flux 103 B4.2. Transition boiling 109 APPENDIX C. DISPERSED FLOW 129 CI. Droplet generation

245

Microjet array single-phase and flow boiling heat transfer with R134a Eric A. Browne a  

E-Print Network [OSTI]

of a submerged microjet array was conducted with R134a. The staggered array of seventeen 112-lm diameter orifices blades and quench metals. Many of these practical uses of jets employ an array of jets rather than circular microjets of diameter 112 lm on a 1 Ã? 1 mm heater to investigate single-phase and boiling heat

Peles, Yoav

246

Advanced turbine cooling, heat transfer, and aerodynamic studies  

SciTech Connect (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

247

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

E-Print Network [OSTI]

Cooling channels with a developing flow entrance condition and aspect ratios of 1:4 and 2:1 were studied. The range of the rotation number and buoyancy parameter for the selected AR channels was extended. The maximum Ro and Bo for the 1:4 channel...

Huh, Michael

2010-01-16T23:59:59.000Z

248

ECI International Conference on Heat Transfer and Fluid Flow in Microscale Whistler, 21-26 September 2008  

E-Print Network [OSTI]

, a measure of the flow conductance of the solid matrix, depends on several factors including: porosity, particles shape and size distribution and particles arrangement. The permeability is calculated either dates back to experimental works of Carman [5] and Sullivan [6] in 1940s and theoretical analyses

Bahrami, Majid

249

Numerical Simulation of Flow and Heat Transfer in Internal Multi-Pass Cooling Channel within Gas Turbine Blade  

E-Print Network [OSTI]

four-pass channel with two different inlet settings. The main flowing channel was rectangular channel (AR=2:1) with hydraulic diameter (Dh ) equals to 2/3 inch (16.9 mm). The first and fourth channel were set as different aspect ratio (AR=2:1; AR=1...

Chu, Hung-Chieh 1979-

2012-11-16T23:59:59.000Z

250

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

SciTech Connect (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

251

Enhanced heat transfer for thermionic power modules  

SciTech Connect (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

252

Numerical simulation of three-dimensional combined convective radiative heat transfer in rectangular channels  

E-Print Network [OSTI]

This dissertation presents a numerical simulation of three-dimensional flow and heat transfer in a channel with a backward-facing step. Flow was considered to be steady, incompressible, and laminar. The flow medium was treated to be radiatively...

Ko, Min Seok

2009-05-15T23:59:59.000Z

253

Finite difference analysis of mass transfer effects on flow past an impulsively started infinite vertical plate in dissipative fluid and constant heat flux  

Science Journals Connector (OSTI)

A finite-difference solution to the flow past an impulsively started infinite vertical plate is derived by assuming 1) presence of species concentration like water vapour, CO2 etc. and 2) constant heat flux at th...

J. N. Das; S. N. Ray; Prof. Dr. V. M. Soundalgekar

1995-02-01T23:59:59.000Z

254

Heat Transfer Laboratory | Argonne National Laboratory  

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

Heat Transfer Laboratory Materials in solids or fluid forms play an important role in a wide range of mechanical systems and vehicle cooling applications. Understanding how...

255

Industrial Steam System Heat-Transfer Solutions  

Broader source: Energy.gov [DOE]

This brief provides an overview of considerations for selecting the best heat-transfer equipment for various steam systems and applications.

256

The influence of a magnetic field on turbulent heat transfer of a high Prandtl number fluid  

E-Print Network [OSTI]

The influence of a magnetic field on turbulent heat transfer of a high Prandtl number fluid H magnetic field on the local and average heat transfer of an electrically conducting, turbulent fluid flow with high Prandtl number was studied experimentally. The mechanism of heat transfer modification due

Abdou, Mohamed

257

6th World Conference on Experimental Heat Transfer, Fluid Mechanics, and Thermodynamics  

E-Print Network [OSTI]

6th World Conference on Experimental Heat Transfer, Fluid Mechanics, and Thermodynamics April 17-21, 2005, Matsushima, Miyagi, Japan Modeling on convective boiling heat transfer in a microtube based visualization, Microchannel, Periodic flow pattern variation 1. INTRODUCTION Convective boiling heat transfer

Kasagi, Nobuhide

258

SINGLE-PHASE LIQUID HEAT TRANSFER IN PLAIN AND ENHANCED MICROCHANNELS Mark E. Steinke  

E-Print Network [OSTI]

SINGLE-PHASE LIQUID HEAT TRANSFER IN PLAIN AND ENHANCED MICROCHANNELS Mark E. Steinke Systems upon the understanding of the fundamental heat transfer processes that occur in these systems. There have been great advancements in our understanding of the heat transfer and fluid flow mechanisms

Kandlikar, Satish

259

Convective heat transfer characteristics of China RP-3 aviation kerosene at supercritical pressure  

E-Print Network [OSTI]

Convective heat transfer characteristics of China RP-3 aviation kerosene at supercritical pressure Keywords: Supercritical pressure Aviation kerosene Convective heat transfer Numerical study a b s t r a c convective in kerosene pipe flow is complicated. Here the convective heat transfer characteristics of China

Guo, Zhixiong "James"

260

Accepted Manuscript A wall heat transfer correlation for the baffled-rotary kilns with secondary air  

E-Print Network [OSTI]

Accepted Manuscript A wall heat transfer correlation for the baffled-rotary kilns with secondary;1 A wall heat transfer correlation for the baffled- rotary kilns with secondary air flow and recycled industrial applications suggests examining the heat transfer phenomena in order to improve the multi

Boyer, Edmond

Note: This page contains sample records for the topic "flow heat transfer" 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

Hypersonic Heat Transfer and Anisotropic Visualization with a Higher Order Discontinuous Galerkin Finite Element Method  

E-Print Network [OSTI]

Hypersonic Heat Transfer and Anisotropic Visualization with a Higher Order Discontinuous Galerkin;Hypersonic Heat Transfer and Anisotropic Visualization with a Higher Order Discontinuous Galerkin Finite used to predict heat transfer to a cylinder in a hypersonic flow. The strong shock is captured

Peraire, Jaime

262

Natural convection heat transfer from two horizontal cylinders  

SciTech Connect (OSTI)

Natural convection heat transfer from a single horizontal cylinder and a pair of vertically aligned horizontal cylinders is investigated. Surface heat transfer distributions around the circumference of the cylinders are presented for Rayleigh numbers of 2 x 10{sup 6}, 4 x 10{sup 6} and 6 x 10{sup 6} and a range of cylinder spacings of 1.5, 2 and 3 diameters. With a cylinder pairing the lower cylinder is unaffected by the presence of the second cylinder; the same is true of the upper cylinder if the lower one is not heated. However, when both cylinders are heated it has been found that a plume rising from the heated lower cylinder interacts with the upper cylinder and significantly affects the surface heat transfer distribution. Spectral analysis of surface heat transfer signals has established the influence of the plume oscillations on the heat transfer. Thus, when the plume from the lower cylinder oscillates out of phase with the flow around the upper cylinder it increases the mixing and results in enhanced heat transfer. (author)

Reymond, Olivier; Murray, Darina B. [Department of Mechanical and Manufacturing Engineering, Trinity College Dublin (Ireland); O'Donovan, Tadhg S. [School of Engineering and Physical Sciences, Heriot-Watt University, Nasmyth Building, Edinburgh EH14 4AS (United Kingdom)

2008-09-15T23:59:59.000Z

263

Effect of alumina nanoparticles in the fluid on heat transfer in double-pipe heat exchanger system  

Science Journals Connector (OSTI)

This study was performed to investigate the convective heat transfer coefficient of nanofluids made of several alumina ... transformer oil which flow through a double pipe heat exchanger system in the laminar flo...

Byung-Hee Chun; Hyun Uk Kang; Sung Hyun Kim

2008-09-01T23:59:59.000Z

264

An experimental study of heat transfer in reciprocating square duct fitted with ribs skewed to the flow  

SciTech Connect (OSTI)

The fuel economy plays the most important requirement for a marine propulsion plant as it has the decisive influence on the operating cost of a ship. In general the improvements of the propulsive and engine efficiencies could reduce the fuel consumption. Therefore, for a marine main diesel engine, the substantial increase of stroke/bore ratio, so that the engine speed can be significantly reduced in order to increase the propulsive efficiency, is observed as a common trend of development in the industry of marine engineering. Along with the efforts in reducing the speed of a propulsive engine, the continuous increases of maximum cycle pressure and temperature of the engine in order to increase the engine efficiency has proceeded in the last decade. As a result, one of the main assemblies of a combustion chamber, the piston, experiences a more difficult working environment. To compensate for the increasing thermal and mechanical loads experienced by a piston, the designs of the piston crown and its cooling system have to be modified. However, due to the reciprocating nature of the piston, the coolant flow circulating within these cooling passages is subjected to an additional time-varied periodical body force induced by reciprocation. Therefore the influences of reciprocating force on the flow field and its cooling performance cannot be ignored if the optimum design of such a cooling system is to be achieved. This study investigated the cooling performance of skewed ribs in the reciprocating duct.

Chang, S.W.; Su, L.M. [National Kaosiung Inst. of Marine Technology (Taiwan, Province of China). Dept. of Marine Engineering; Yang, T.L.; Hwang, C.C. [National Cheng Kung Univ., Tainan (Taiwan, Province of China). Dept. of Naval Architecture and Marine Engineering

1999-02-01T23:59:59.000Z

265

Computation of fluid circulation in a cryogenic storage tank and heat transfer analysis during jet impingement.  

E-Print Network [OSTI]

??The study presents a systematic single and two-phase analysis of fluid flow and heat transfer in a liquid hydrogen storage vessel for both earth and… (more)

Mukka, Santosh Kumar

2005-01-01T23:59:59.000Z

266

A phase-field method for 3D simulation of two-phase heat transfer  

E-Print Network [OSTI]

stationary grids, different modes of heat transfer (e.g. convection/conduction), as well as its ... flow systems with sharp-interface models, moving-grid methods.

X. Zheng

2014-12-04T23:59:59.000Z

267

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 infor multiphase fluid flow, heat transfer and deformation in

Rutqvist, J.

2011-01-01T23:59:59.000Z

268

Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow...  

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

Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer, Longer-lasting Batteries Colorado: Isothermal Battery Calorimeter Quantifies Heat Flow, Helps Make Safer,...

269

Inr J Heat Mass Transfer. Vol. 39. No. 15, pp. 3165-3173, 1996 Copyright 0 1996 Elsevier Science Ltd  

E-Print Network [OSTI]

is described by a temperature transforming model coupled to the heat transfer from the transfer fluid. The heat the heat transfer in thermal energy storage systems when a fluid with a low thermal conductivity is used space around the tube, while the transfer fluid flows within the tube. This type of latent heat storage

Zhang, Yuwen

270

Heat transfer characteristics of fluidized bed heat exchanger in a 300 MW CFB boiler  

Science Journals Connector (OSTI)

In order to investigate the heat transfer characteristics of fluidized bed heat exchanger (FBHE), a series of experiments was carried out in a commercial 300 MW circulating fluidized bed (CFB) boiler with FBHE. The parameters of steam, solids and air in FBHE were measured at different boiler loads, based on which the absorbed heat and heat transfer coefficient were calculated. Further study indicates that when the calculated results are applied to the design of large-scale CFB boilers, the bed side heat transfer coefficient in FBHE can be simplified as the function of solids temperature and flow. Therefore, the empirical model of heat transfer coefficient at bed side is put forward. The deviation between calculated results and measured values is acceptable in engineering application. This model provides strong support for the FBHE design in 600 MW supercritical CFB boilers.

Man Zhang; Haibo Wu; Qinggang Lu; Yunkai Sun; Guoliang Song

2012-01-01T23:59:59.000Z

271

Cryogenic heat exchanger with turbulent flows  

Science Journals Connector (OSTI)

An evaporator-type cryogenic heat exchanger is designed and built for introducing fluid–solid heat exchange phenomena to undergraduates in a practical and efficient way. The heat exchanger functions at liquid nitrogen temperature and enables cooling of N2 and He gases from room temperatures. We present first the experimental results of various parameters which characterize the heat exchanger (efficiency, number of transfer units, heat exchange coefficient, etc) as a function of the mass flow rate of the gas to be cooled. An analysis of the Nu–Re diagram is also presented. All experiments were conducted with N2 gas. The scope of this tool is readily extended to research purposes.

Jay Amrit; Christelle Douay; Francis Dubois; Gérard Defresne

2012-01-01T23:59:59.000Z

272

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

273

"Nanotechnology Enabled Advanced Industrial Heat Transfer Fluids"  

SciTech Connect (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

274

Multidimensional mechanistic modeling of interfacial heat and mass transfer  

SciTech Connect (OSTI)

A combined theoretical and computational study in modeling multidimensional, diabatic vapor/liquid flows is presented. Models have been developed governing kinematic aspects of multiphase flow as well as interfacial mass and heat transfer for flows of condensable gas (vapor) and liquids. The modeling formulation is based on the Reynolds averaged Navier-Stokes (RANS) type multi-field approach which utilizes a complete set of conservation equations for each fluid component 1. The modeled interfacial interactions include energy, mass, and momentum transfer. Emphasis in the model development work has been placed on the mechanisms governing coupled interfacial heat and mass transfer between the liquid and vapor fields (condensation and/or boiling). A method for tracking changes in bubble size is presented and tested. Locally based models of multidimensional effects have been analyzed, including distributions of fluid temperatures and volume fractions. The overall model accounts for both kinematic and thermodynamic nonequilibrium between the component fluids including superheated vapor. The model has been implemented in the NPHASE-CMFD computer code. Results from the kinematic model are compared to experimental data and good agreement is demonstrated. The heat and mass transfer model is parametrically tested to show the multidimensional effects on the rate of heat and mass transfer. These effects are explained in terms of local characteristics of the two-phase flow. The model is applied to a scenario of saturated vapor injected into a subcooled flow through a heated, porous wall. This provides a reasonable approximation to subcooled boiling. The results are found to be dependent on the partitioning of the wall heat flux between direct liquid heating and vapor generation. However, the observed dependencies are explained and the modeling is considered consistent. (authors)

Shaver, D. R.; Antal, S. P.; Podowski, M. Z. [Center for Multiphase Research, Rensselaer Polytechnic Inst., Troy, NY (United States)

2012-07-01T23:59:59.000Z

275

Transient critical heat flux and blowdown heat-transfer studies  

SciTech Connect (OSTI)

Objective of this study is to give a best-estimate prediction of transient critical heat flux (CHF) during reactor transients and hypothetical accidents. To accomplish this task, a predictional method has been developed. Basically it involves the thermal-hydraulic calculation of the heated core with boundary conditions supplied from experimental measurements. CHF predictions were based on the instantaneous ''local-conditions'' hypothesis, and eight correlations (consisting of round-tube, rod-bundle, and transient correlations) were tested against most recent blowdown heat-transfer test data obtained in major US facilities. The prediction results are summarized in a table in which both CISE and Biasi correlations are found to be capable of predicting the early CHF of approx. 1 s. The Griffith-Zuber correlation is credited for its prediction of the delay CHF that occurs in a more tranquil state with slowly decaying mass velocity. In many instances, the early CHF can be well correlated by the x = 1.0 criterion; this is certainly indicative of an annular-flow dryout-type crisis. The delay CHF occurred at near or above 80% void fraction, and the success of the modified Zuber pool-boiling correlation suggests that this CHF is caused by flooding and pool-boiling type hydrodynamic crisis.

Leung, J.C.

1980-05-01T23:59:59.000Z

276

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

277

Rod Bundle Heat Transfer: Steady-State Steam Cooling Experiments  

SciTech Connect (OSTI)

Through the joint efforts of the Pennsylvania State University and the United States Nuclear Regulatory Commission, an experimental rod bundle heat transfer (RBHT) facility was designed and built. The rod bundle consists of a 7 x 7 square pitch array with spacer grids and geometry similar to that found in a modern pressurized water reactor. From this facility, a series of steady-state steam cooling experiments were performed. The bundle inlet Reynolds number was varied from 1 400 to 30 000 over a pressure range from 1.36 to 4 bars (20 to 60 psia). The bundle inlet steam temperature was controlled to be at saturation for the specified pressure and the fluid exit temperature exceeded 550 deg. C in the highest power tests. One important quantity of interest is the local convective heat transfer coefficient defined in terms of the local bulk mean temperature of the flow, local wall temperature, and heat flux. Steam temperatures were measured at the center of selected subchannels along the length of the bundle by traversing miniaturized thermocouples. Using an analogy between momentum and energy transport, a method was developed for relating the local subchannel centerline temperature measurement to the local bulk mean temperature. Wall temperatures were measured using internal thermocouples strategically placed along the length of each rod and the local wall heat flux was obtained from an inverse conduction program. The local heat transfer coefficient was calculated from the data at each rod thermocouple location. The local heat transfer coefficients calculated for locations where the flow was fully developed were compared against several published correlations. The Weisman and El-Genk correlations were found to agree best with the RBHT steam cooling data, especially over the range of turbulent Reynolds numbers. The effect of spacer grids on the heat transfer enhancement was also determined from instrumentation placed downstream of the spacer grid locations. The local heat transfer was found to be greatest at locations immediately downstream of the grid, and as the flow moved further downstream from the grid it became more developed, thus causing the heat transfer to diminish. The amount of heat transfer enhancement was found to depend not only on the spacer grid design, but also on the local Reynolds number. It was seen that decreasing Reynolds number leads to greater heat transfer enhancement. (authors)

Spring, J.P.; McLaughlin, D.M. [The Pennsylvania State University, 201 Shields Building University Park, PA 16802 (United States)

2006-07-01T23:59:59.000Z

278

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

279

The effect of velocity boundary conditions on the heat transfer and flow topology in two-dimensional Rayleigh-B\\'enard convection  

E-Print Network [OSTI]

The effect of various velocity boundary condition is studied in two-dimensional Rayleigh-B\\'enard convection. Combinations of no-slip, stress-free and periodic boundary conditions are used on both the sidewalls and the horizontal plates. For the studied Rayleigh numbers Ra between $10^8$ and $10^{11}$ the heat transport is lower for $\\Gamma = 0.33$ than for $\\Gamma = 1$ in case of no-slip sidewalls. This is surprisingly opposite for stress-free sidewalls, where the heat transport increases for lower aspect-ratio. In wider cells the aspect-ratio dependence is observed to disappear for $\\text{Ra} \\ge 10^{10}$. Two distinct flow types with very different dynamics can be seen, mostly dependent on the plate velocity boundary condition, namely roll-like flow and horizontal zonal flow, which have a substantial effect on the dynamics and heat transport in the system. The predominantly horizontal zonal flow suppresses heat flux and is observed for stress-free and asymmetric plates. Low aspect-ratio periodic sidewall s...

van der Poel, Erwin P; Verzicco, Roberto; Lohse, Detlef

2015-01-01T23:59:59.000Z

280

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

Note: This page contains sample records for the topic "flow heat transfer" 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

Clean Boiler Waterside Heat Transfer Surfaces  

SciTech Connect (OSTI)

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.

Not Available

2006-01-01T23:59:59.000Z

282

Clean Boiler Waterside Heat Transfer Surfaces  

Broader source: Energy.gov [DOE]

This 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.

283

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

284

Project Profile: Dual-Purpose Heat Transfer Fluids for CSP  

Broader source: Energy.gov [DOE]

Argonne National Laboratory, under an ARRA CSP Award, is developing advanced heat transfer fluids (HTFs) by incorporating multifunctional engineered nanoparticles in heat transfer applications and thermal energy storage.

285

Nanoparticle enhanced ionic liquid heat transfer fluids  

DOE Patents [OSTI]

A heat transfer fluid created from nanoparticles that are dispersed into an ionic liquid is provided. Small volumes of nanoparticles are created from e.g., metals or metal oxides and/or alloys of such materials are dispersed into ionic liquids to create a heat transfer fluid. The nanoparticles can be dispersed directly into the ionic liquid during nanoparticle formation or the nanoparticles can be formed and then, in a subsequent step, dispersed into the ionic liquid using e.g., agitation.

Fox, Elise B.; Visser, Ann E.; Bridges, Nicholas J.; Gray, Joshua R.; Garcia-Diaz, Brenda L.

2014-08-12T23:59:59.000Z

286

ME 339 Heat Transfer ABET EC2000 syllabus  

E-Print Network [OSTI]

ME 339­ Heat Transfer Page 1 ABET EC2000 syllabus ME 339 ­ Heat Transfer Spring 2010 Required convection; radiation; introduction to phase change heat transfer and to heat exchangers. Prerequisite(s): ME, Fundamentals of Heat and Mass Transfer, 6th ed., Wiley Other Required Material: NA Course Objectives

Ben-Yakar, Adela

287

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

Open Energy Info (EERE)

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

288

Examination of Liquid Fluoride Salt Heat Transfer  

SciTech Connect (OSTI)

The need for high efficiency power conversion and energy transport systems is increasing as world energy use continues to increase, petroleum supplies decrease, and global warming concerns become more prevalent. There are few heat transport fluids capable of operating above about 600oC that do not require operation at extremely high pressures. Liquid fluoride salts are an exception to that limitation. Fluoride salts have very high boiling points, can operate at high temperatures and low pressures and have very good heat transfer properties. They have been proposed as coolants for next generation fission reactor systems, as coolants for fusion reactor blankets, and as thermal storage media for solar power systems. In each case, these salts are used to either extract or deliver heat through heat exchange equipment, and in order to design this equipment, liquid salt heat transfer must be predicted. This paper discusses the heat transfer characteristics of liquid fluoride salts. Historically, heat transfer in fluoride salts has been assumed to be consistent with that of conventional fluids (air, water, etc.), and correlations used for predicting heat transfer performance of all fluoride salts have been the same or similar to those used for water conventional fluids an, water, etc). A review of existing liquid salt heat transfer data is presented, summarized, and evaluated on a consistent basis. Less than 10 experimental data sets have been found in the literature, with varying degrees of experimental detail and measured parameters provided. The data has been digitized and a limited database has been assembled and compared to existing heat transfer correlations. Results vary as well, with some data sets following traditional correlations; in others the comparisons are less conclusive. This is especially the case for less common salt/materials combinations, and suggests that additional heat transfer data may be needed when using specific salt eutectics in heat transfer equipment designs. All of the data discussed above were taken under forced convective conditions (both laminar and turbulent). Some recent data taken at ORNL under free convection conditions are also presented and results discussed. This data was taken using a simple crucible experiment with an instrumented nickel heater inserted in the salt to induce natural circulation within the crucible. The data was taken over a temperature range of 550oC to 650oC in FLiNaK salt. This data covers both laminar and turbulent natural convection conditions, and is compared to existing forms of natural circulation correlations.

Yoder Jr, Graydon L [ORNL] [ORNL

2014-01-01T23:59:59.000Z

289

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

290

Numerical simulation of the heat transfer in amorphous silicon nitride membrane-based microcalorimeters  

E-Print Network [OSTI]

Numerical simulation of the heat transfer in amorphous silicon nitride membrane July 2003 Numerical simulations of the two-dimensional 2D heat flow in a membrane-based microcalorimeter have been performed. The steady-state isotherms and time-dependent heat flow have been calculated

Hellman, Frances

291

A FULL SCALE ROOM FOR THE EXPERIMENTAL STUDY OF INTERIOR BUILDING CONVECTIVE HEAT TRANSFER  

E-Print Network [OSTI]

air flow measurement. A water source heat pump provided chilled water to a fan-coil unit which in turn on volumetric air flow measurement and an overall room heat balance. Analysis was directed at results fromA FULL SCALE ROOM FOR THE EXPERIMENTAL STUDY OF INTERIOR BUILDING CONVECTIVE HEAT TRANSFER: DESIGN

292

Heat transfer with nanofluids for electronic cooling  

Science Journals Connector (OSTI)

In response to the ever increasing demand for smaller and lighter high performance cooling devices a new heat transfer liquids come into picture, called Nanofluids. Nanofluids are new class of heat transfer fluids developed by suspending nanosized solid particles in liquids. Larger thermal conductivity of solid particles compared to the base fluid such as water, ethylene glycol, engine oil, etc. significantly enhances its thermal properties. Numbers of phenomenological models have been proposed to explain the anomalous heat transfer enhancement in nanofluids. This paper presents systematic literature survey observed to exploit several characteristic behaviours of nanofluids viz. increase in thermal conductivity, specific heat and other thermal properties. An empirical correlation for Al2O3 + water nanofluid and effects of temperature, volume fraction and size of nanoparticle is studied. The effect of temperature on nanofluid thermal conductivity is also brought out. This behaviour combined with better mechanical properties makes fluids embedded with nanomaterials are excellent candidates for future applications.

V. Vasu; K Rama Krishna; A.C.S. Kumar

2009-01-01T23:59:59.000Z

293

A Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow Measurements  

Open Energy Info (EERE)

Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow Measurements Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow Measurements And Heat-Flow Estimates From The Uk Geothermal Catalogue Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Simple Heat-Flow Quality Function And Appraisal Of Heat-Flow Measurements And Heat-Flow Estimates From The Uk Geothermal Catalogue Details Activities (0) Areas (0) Regions (0) Abstract: A comprehensive database of temperature, heat flow, thermal conductivity and geochemistry is the basis of geothermal modelling. The latest revision (1987) of the UK Geothermal Catalogue (UKGC) contains over 2600 temperatures at over 1150 sites and over 200 observations of heat flow. About 93% of the temperature data are from depths less than 2000 m and about 50% are Bottom Hole Temperatures (BHT). Heat-flow density

294

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

295

Heat Transfer Enhancement for Finned-tube Heat Exchangers with Winglets  

SciTech Connect (OSTI)

This paper presents the results of an experimental study of forced convection heat transfer in a narrow rectangular duct fitted with a circular tube and/or a delta-winglet pair. The duct was designed to simulate a single passage in a fin-tube heat exchanger. Heat transfer measurements were obtained using a transient technique in which a heated airflow is suddenly introduced to the test section. High-resolution local fin-surface temperature distributions were obtained at several times after initiation of the transient using an imaging infrared camera. Corresponding local fin-surface heat transfer coefficient distributions were then calculated from a locally applied one-dimensional semi-infinite inverse heat conduction model. Heat transfer results were obtained over an airflow rate ranging from 1.51 x 10-3 to 14.0 x 10-3 kg/s. These flow rates correspond to a duct-height Reynolds number range of 670 – 6300 with a duct height of 1.106 cm and a duct width-toheight ratio, W/H, of 11.25. The test cylinder was sized such that the diameter-to-duct height ratio, D/H is 5. Results presented in this paper reveal visual and quantitative details of local fin-surface heat transfer distributions in the vicinity of a circular tube, a delta-winglet pair, and a combination of a circular tube and a delta-winglet pair. Comparisons of local and average heat transfer distributions for the circular tube with and without winglets are provided. Overall mean finsurface Nusselt-number results indicate a significant level of heat transfer enhancement associated with the deployment of the winglets with the circular cylinder. At the lowest Reynolds numbers (which correspond to the laminar operating conditions of existing geothermal air-cooled condensers), the enhancement level is nearly a factor of two. At higher Reynolds numbers, the enhancement level is close to 50%.

O'Brien, James Edward; Sohal, Manohar Singh

2000-11-01T23:59:59.000Z

296

Numerical Simulations of Bubble Dynamics and Heat Transfer in Pool Boiling--Including the Effects of Conjugate Conduction, Level of Gravity, and Noncondensable Gas Dissolved in the Liquid  

E-Print Network [OSTI]

flow boiling. ” Journal of heat transfer, 124(4), 4. Basu,Dhir, V. K. (2005). “Wall heat flux partitioning duringdevelopment. ” Journal of Heat Transfer, 127(2), 5. Carey

Aktinol, Eduardo

2014-01-01T23:59:59.000Z

297

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

298

Including radiative heat transfer and reaction quenching in modeling a Claus plant waste heat boiler  

SciTech Connect (OSTI)

Due to increasingly stringent sulfur emission regulations, improvements are necessary in the modified Claus process. A recently proposed model by Nasato et al. for the Claus plant waste heat boiler (WHB) is improved by including radiative heat transfer, which yields significant changes in the predicted heat flux and the temperature profile along the WHB tube, leading to a faster quenching of chemical reactions. For the WHB considered, radiation accounts for approximately 20% of the heat transferred by convection alone. More importantly, operating the WHB at a higher gas mass flux is shown to enhance reaction quenching, resulting in a doubling of the predicted hydrogen flow rate. This increase in hydrogen flow rate is sufficient to completely meet the hydrogen requirement of the H[sub 2]S recovery process considered, which would eliminate the need for a hydrogen plant.

Karan, K.; Mehrotra, A.K.; Behie, L.A. (Univ. of Calgary, Alberta (Canada). Dept. of Chemical and Petroleum Engineering)

1994-11-01T23:59:59.000Z

299

Heat transfer in a visco-elastic fluid past a stretching sheet with viscous dissipation and internal heat generation  

Science Journals Connector (OSTI)

This paper deals with the study of heat transfer characteristics in the laminar boundary layer flow of a visco-elastic fluid over a linearly stretching continuous surface with ... . The study considers the effect...

P. H. Veena; Subhash Abel; K. Rajagopal…

2006-05-01T23:59:59.000Z

300

Potassium, Uranium, Thorium Radiogenic Heat Contribution To Heat Flow In  

Open Energy Info (EERE)

Potassium, Uranium, Thorium Radiogenic Heat Contribution To Heat Flow In Potassium, Uranium, Thorium Radiogenic Heat Contribution To Heat Flow In The Precambrian And Younger Silicic Rocks Of The Zuni And Florida Mountains, New Mexico (Usa) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Potassium, Uranium, Thorium Radiogenic Heat Contribution To Heat Flow In The Precambrian And Younger Silicic Rocks Of The Zuni And Florida Mountains, New Mexico (Usa) Details Activities (4) Areas (2) Regions (0) Abstract: High heat flow in the Zuni Mountains, New Mexico, U.S.A., has been explained by the possible presence of a buried felsic pluton. Alternately, high K, U, Th abundances have been proposed to account for part of the high heat flow. The mean radiogenic heat contribution for 60 samples of Precambrian core rocks is 7.23 μcal/gm-yr, which is slightly

Note: This page contains sample records for the topic "flow heat transfer" 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

Analysis of heat transfer in unlooped and looped pulsating  

E-Print Network [OSTI]

Analysis of heat transfer in unlooped and looped pulsating heat pipes M.B. Sha®i and A. Faghri of Mechnical Engineering, New Mexico State University, Las Cruces, USA Keywords Heat transfer, Condensation, Tubing Abstract An advanced heat transfer model for both unlooped and looped Pulsating Heat Pipes (PHPs

Zhang, Yuwen

302

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

303

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

Energy Savers [EERE]

Geothermal Heat Flow and Existing Geothermal Plants Geothermal Heat Flow and Existing Geothermal Plants Geothermal Heat Flow and Existing Plants With plants in development. Click...

304

Heat Transfer in Liquid Helium below 1 degrees K  

Science Journals Connector (OSTI)

...September 1955 research-article Heat Transfer in Liquid Helium below 1 degrees...is proportional to the specific heat and the diameter of the specimen. Thus the sole mechanism of heat transfer appears to be by phonons which...

1955-01-01T23:59:59.000Z

305

Heat Transfer and Fluid Mechanics for Laser Machining  

Science Journals Connector (OSTI)

This chapter introduces some of the basic concepts in heat transfer, fluid mechanics and numerical solution methods. Since laser ... process, an understanding of issues in conduction heat transfer, convection heat

George Chryssolouris

1991-01-01T23:59:59.000Z

306

HEAT TRANSFER IN POROUS MEDIA WITH FLUID PHASE CHANGES  

E-Print Network [OSTI]

R. T. , and Kesaran, K. : "Heat Transfer From CylindersProc. of 4th Internal. Heat Transfer Conference, Paris-Cotter, T. P. : "Theory of Heat Pipe," Report No. LA-3246-

Su, Ho-Jeen.

2010-01-01T23:59:59.000Z

307

Simulation of heat transfer in the unsaturated zone  

SciTech Connect (OSTI)

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

308

Heat transfer analysis in Stirling engine heat input system  

SciTech Connect (OSTI)

One of the major factor in commercialization of Stirling engine is mass productivity, and the heat input system including tubular heater is one of the obstacles to mass production because of its complexity in shape and difficulty in manufacturing, which resulted from using oxidation-resistant, low-creep alloys which are not easy to machine and weld. Therefore a heater heat exchanger which is very simple in shape and easy to make has been devised, and a burner system appropriate to this heater also has been developed. In this paper specially devised heat input system which includes a heater shell shaped like U-cup and a flame tube located in the heater shell is analyzed in point of heat transfer processes to find optimum heat transfer. To enhance the heat transfer from the flame tube to the heater shell wall, it is required that the flame tube diameter be enlarged as close to the heater shell diameter as possible, and the flame tube temperature be raised as high as possible. But the enlargement of the flame tube diameter should be restricted by the state of combustion affected by hydraulic resistance of combustion gas, and the boost of the flame tube temperature should be considered carefully in the aspects of the flame tube`s service life.

Chung, W.; Kim, S. [LG Electronics Inc., Seoul (Korea, Republic of). Living System Lab.

1995-12-31T23:59:59.000Z

309

Heat transfer studies. Quarterly report  

SciTech Connect (OSTI)

Nitrogen gas has been used in experimental studies related to understanding issues in the extension of multi-phase models to sub-residual saturation conditions during drying. Two different flow rates of 1 SLPM and 0.5 SLPM with a room temperature boundary condition on the aluminum column have been examined. Information about variations of humidity and temperatures is given. It is shown that the situation that exists in the experiments is somewhat different than that found in typical assumptions made by numerical modelers. Work planned for the next quarter is outlined. The apparatus used for the work noted above will be supplemented to allow other temperature conditions than ambient to be evaluated. Temperatures up to 90{degree}C will be used. Other work planned for the next period will involve the use of small-scale simulated repository experiment to determine temperatures and humidities around a horizontal heater within an annulus in a rigid porous medium. The effect of backfill on performance when episodic flows are encountered will be compared to results when backfill is not present (the latter results have been determined earlier).

Boehm, R.; Chen, Y.T.; Vallebuona, J.

1995-07-20T23:59:59.000Z

310

Self supporting heat transfer element  

DOE Patents [OSTI]

The present invention provides an improved internal heat exchange element arranged so as to traverse the inside diameter of a container vessel such that it makes good mechanical contact with the interior wall of that vessel. The mechanical element is fabricated from a material having a coefficient of thermal conductivity above about 0.8 W cm.sup.-1.degree. K.sup.-1 and is designed to function as a simple spring member when that member has been cooled to reduce its diameter to just below that of a cylindrical container or vessel into which it is placed and then allowed to warm to room temperature. A particularly important application of this invention is directed to a providing a simple compartmented storage container for accommodating a hydrogen absorbing alloy.

Story, Grosvenor Cook (Livermore, CA); Baldonado, Ray Orico (Livermore, CA)

2002-01-01T23:59:59.000Z

311

Heat Transfer -1 You are given the following information for a fluid with thermal conductivity of k = 0.0284 W/m-K that  

E-Print Network [OSTI]

Heat Transfer - 1 You are given the following information for a fluid with thermal conductivity the flow is laminar near the wall. a) (30 points) Determine the corresponding heat transfer coefficient the heat transfer coefficient as a function of x. c) (25 points) Determine the average heat transfer

Virginia Tech

312

Oscillating flow in a stirling engine heat exchanger  

Science Journals Connector (OSTI)

Three heat exchangers exist in modern Stirling engines: a heater, a cooler, and a regenerator. Here a study that deals principally with tubular heaters and coolers is carried out. The calculation procedure for the oscillating flow heat transfer is presented. Literature sources are studied to find the most suitable correlations by comparing them to each other and to the classical turbulent flow correlations encountered in the literature. The enhancement of heat transfer by means of a few circumferential slots inside the tubes and the pressure losses of oscillatory flow are discussed. Non-circular cross-section conduits with rectangular and triangular cross-sections are investigated and compared to the smooth circular tubes. The increment of the performance of an idealised Stirling engine with slotted heat exchanger tubes is compared to the case with smooth ones. The ratio of the gain in the shaft power and pumping losses is 2.22. The Carnot efficiency increment is 2.7%.

M. Kuosa; K. Saari; A. Kankkunen; T.-M. Tveit

2012-01-01T23:59:59.000Z

313

Local Heat Transfer for Finned-Tube Heat Exchangers using Oval Tubes  

SciTech Connect (OSTI)

This paper presents the results of an experimental study of forced convection heat transfer in a narrow rectangular duct fitted with either a circular tube or an elliptical tube in crossflow. The duct was designed to simulate a single passage in a fin-tube heat exchanger. Heat transfer measurements were obtained using a transient technique in which a heated airflow is suddenly introduced to the test section. High-resolution local fin-surface temperature distributions were obtained at several times after initiation of the transient using an imaging infrared camera. Corresponding local fin-surface heat transfer coefficient distributions were then calculated from a locally applied one-dimensional semi-infinite inverse heat conduction model. Heat transfer results were obtained over an airflow rate ranging from 1.56 x 10-3 to 15.6 x 10-3 kg/s. These flow rates correspond to a duct-height Reynolds number range of 630 – 6300 with a duct height of 1.106 cm and a duct width-toheight ratio, W/H, of 11.25. The test cylinder was sized such that the diameter-to-duct height ratio, D/H is 5. The elliptical tube had an aspect ratio of 3:1 and a/H equal to 4.33. Results presented in this paper reveal visual and quantitative details of local fin-surface heat transfer distributions in the vicinity of circular and oval tubes and their relationship to the complex horseshoe vortex system that forms in the flow stagnation region. Fin surface stagnation-region Nusselt numbers are shown to be proportional to the square-root of Reynolds number.

O'Brien, James Edward; Sohal, Manohar Singh

2000-08-01T23:59:59.000Z

314

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

315

Heat transfer research on gas turbine airfoils at NASA GRC  

Science Journals Connector (OSTI)

The turbine gas path is a very complex flow field due to a variety of flow and heat transfer phenomena encountered in turbine passages. This manuscript provides an overview of the current work in this field at the NASA Glenn Research Center (GRC). Based on the author's preference, however, more emphasis is on the computational work. There is much more experimental work in progress at GRC than that reported here. Specifically, the external flow and heat transfer characteristics are described over smooth and rough turbine blades for a range of parameter values. For smooth blades, the effect of film-cooling holes as well as internal cooling channels with ribs and bleed holes is considered. Studies on the blade tip region, susceptible to burnout and oxidation due to high thermal loading, are also described. Wherever possible, predictions of heat transfer coefficient on the real blade surface, obtained using in-house-developed codes, are compared with the available experimental data. Suggestions for further work are outlined.

Vijay K. Garg

2002-01-01T23:59:59.000Z

316

Experimental and numerical study of laminar forced convection heat transfer for a dimpled heat sink  

E-Print Network [OSTI]

characteristics in a laminar and a turbulent airflow condition. A relative dimple depth in the range of 0.06 to 0.24 and a SIMPLEC (Semi-Implicit Method for Pressure-Linked Equations) method with multiblock grids were used to evaluate the flow change and heat....3) 4.3 Computation Procedure The computations of the fluid flow field and heat transfer were performed using CFD by Fluent software, version Fluent 6.2.16. Gambit 2.2.30 was used for the development of the computational grid. 4.3.1 Computational...

Park, Do Seo

2009-05-15T23:59:59.000Z

317

International contributions to IAEA-NEA heat transfer databases for supercritical fluids  

SciTech Connect (OSTI)

An IAEA Coordinated Research Project on 'Heat Transfer Behaviour and Thermohydraulics Code Testing for SCWRs' is being conducted to facilitate collaboration and interaction among participants from 15 organizations. While the project covers several key technology areas relevant to the development of SCWR concepts, it focuses mainly on the heat transfer aspect, which has been identified as the most challenging. Through the collaborating effort, large heat-transfer databases have been compiled for supercritical water and surrogate fluids in tubes, annuli, and bundle subassemblies of various orientations over a wide range of flow conditions. Assessments of several supercritical heat-transfer correlations were performed using the complied databases. The assessment results are presented. (authors)

Leung, L. K. H. [Atomic Energy of Canada Limited, Chalk River Laboratories, Chalk River, ON K0J 1J0 (Canada); Yamada, K. [International Atomic Energy Agency, Vienna International Centre, P.O. Box 100, 1400 Vienna (Austria)

2012-07-01T23:59:59.000Z

318

An experimental study on heat transfer from a horizontal heated circular cylinder enhanced by water spray.  

E-Print Network [OSTI]

??A series of experiments were conducted to investigate the heat transfer which occurs with a heated, constant heat flux, horizontal, single circular cylinder is exposed… (more)

Chau, Man Hei

2009-01-01T23:59:59.000Z

319

Heat flow on the southern Colorado Plateau  

Science Journals Connector (OSTI)

Heat-flow data from the study area in the southern Colorado Plateau indicate a pattern of local anomalies having relatively high heat flow superimposed on a regional, intermediate heat-flow setting. While many of the conventional heat-flow data are relatively shallow and may be perturbed by groundwater circulation, bottom-hole temperature data from two relatively deep petroleum exploration drill holes near the southern plateau periphery yield intermediate heat-flow estimates. The mean heat flow within the volcanically active Jemez zone does not appear to be significantly greater than the mean heat flow for the remainder of the study area. This is due to the presence of high heat-flow values outside the Jemez zone. Sites with relatively high heat flow located towards the plateau interior and away from recent volcanic activity of the Jemez zone may reflect magma intrusion and/or groundwater movement along crustal zones of weakness associated with Laramide deformation (monoclines). The heat-flow data are consistent with coal maturation data, which suggest that any regional post-Cretaceous thermal events that may be associated with the southern Plateau boundary have been initiated relatively recently, or are occurring at relatively great depths, or are occurring south of the Jemez lineament.

Jeffrie Minier; Marshall Reiter

1991-01-01T23:59:59.000Z

320

Heat and mass transfer of moist air in vertical channels  

SciTech Connect (OSTI)

Natural convection heat transfer in vertical open channel flows has been widely studied for various geometric configurations since it concerns a number of applications, ranging from the cooling of electronic equipment to the heating of buildings. This study examines energy transport associated with liquid film condensation or evaporation in natural convection flows driven by differences in density due to temperature and concentration gradients. The most common compositional gradient which is encountered in humid air is considered. A steady, laminar, Boussinesq flow of an ideal gas-vapor mixture is studied for the case of a vertical open plane channel. The influence of the species interdiffusion due to enthalpy difference between air and water vapor is considered first in the case of evaporation. It is shown that the species interdiffusion term is negligible even at moderate temperature differences. This study mainly investigates wall condensation of humid air and preliminary results are presented.

Desrayaud, G.; Garnier, V.; Lauriat, G.

1999-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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
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321

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

322

Thermoacoustic device for nuclear fuel monitoring and heat transfer enhancement  

Science Journals Connector (OSTI)

The Fukushima Dai’ichi nuclear disaster of 2011 exposed the need for self-powered sensors that could transmit the status of the fuel rods within the reactor and in spent fuel ponds that was not dependent upon availability of external electrical power for either sensing or telemetry. One possible solution is the use of a thermoacoustic standing wave engine incorporated within a fuel rod which is heated by the nuclear fuel. The engine’s resonance frequency is correlated to the fuel rod temperature and will be transmitted by sound radiation through the reactor's or storage pond’s surrounding water. In addition to acting as a passive temperature sensor the thermoacoustic device will serve to enhance heat transfer from the fuel to the surrounding heat transfer fluid. When activated the acoustically-driven streaming flow of the gas within the fuel rod will circulate gas away from the nuclear fuel and convectively enhance heat transfer to the surrounding coolant. We will present results for a thermoacousticresonator built into a Nitonic® 60 (stainless steel) fuel rod that can be substituted for conventional fuel rods in the Idaho National Laboratory’s Advanced Test Reactor. This laboratory version is heated electrically. [Work supported by the U.S. Department of Energy.

Randall A. Ali; Steven L. Garrett; James A. Smith; Dale K. Kotter

2012-01-01T23:59:59.000Z

323

Heat transfer from a continuous surface in a parallel free stream of viscoelastic fluid  

Science Journals Connector (OSTI)

The effect of uniform suction or injection on flow and heat transfer from a continuous surface in a parallel free stream of viscoelastic second-order fluid is investigated. A perturbation method is used ... profi...

Dr. F. M. Hady; Dr. R. S. R. Gorla

1998-01-01T23:59:59.000Z

324

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...

Yu, Jiwon 1982-

2012-12-03T23:59:59.000Z

325

The influence of return bends on the downstream pressure drop and condensation heat transfer in tubes  

E-Print Network [OSTI]

The influence of return bends on the downstream pressure drop and heat transfer coefficient of condensing refrigerant R-12 was studied experimentally. Flow patterns in glass return bends of 1/2 to 1 in. radius and 0.315 ...

Traviss, Donald P.

1971-01-01T23:59:59.000Z

326

Heat and Mass Transfer Wrme-und Stoffbertragung  

E-Print Network [OSTI]

1 23 Heat and Mass Transfer Wärme- und Stoffübertragung ISSN 0947-7411 Volume 49 Number 3 Heat Mass

Guo, Zhixiong "James"

327

Advanced Heat Transfer Fluids and Novel Thermal Storage Concepts...  

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

Systems Lehigh University: Novel Thermal Storage Technologies for Concentrating Solar Power Generation Terrafore: Heat Transfer and Latent Heat Storage in Inorganic Molten...

328

INVESTIGATING THE EFFECT OF HEATING METHOD ON POOL BOILING HEAT TRANSFER  

E-Print Network [OSTI]

INVESTIGATING THE EFFECT OF HEATING METHOD ON POOL BOILING HEAT TRANSFER Satish G. Kandlikar surfaces in laboratories to obtain the heat transfer coefficient data. In many process applications however, a fluid stream is employed as the heating medium. The heat transfer data generated with the electrically

Kandlikar, Satish

329

Heat Transfer Enhancement: Second Generation Technology  

E-Print Network [OSTI]

stant temperature difference or one-ninth the temp erature difference at a constant heat flux compared to plain tubes. 7.5 frn/em lin tube Atter flanening ltn tips Some manufacturers also employ tube-side en hancement for water flowing...

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

1984-01-01T23:59:59.000Z

330

Heat Transfer by Free Convection in a Liquid Metal  

Science Journals Connector (OSTI)

19 December 1961 research-article Heat Transfer by Free Convection in a Liquid Metal F. J. Bayley...an experimental investigation of the free convection heat transfer process under the special conditions associated with...

1961-01-01T23:59:59.000Z

331

Heat Transfer from an Air-Cooled Rotating Disk  

Science Journals Connector (OSTI)

19 February 1974 research-article Heat Transfer from an Air-Cooled Rotating Disk J. M. Owen C...theoretical and experimental investigation into the heat transfer from a disk rotating close to a stator with a radial...

1974-01-01T23:59:59.000Z

332

Heat transfer and fluid friction in bundles of twisted tubes  

Science Journals Connector (OSTI)

The results of heat-transfer and friction studies in bundles of twisted tubes and rods with spiral wire-wrap spacers are analyzed, and recommendations are given for calculating the heat-transfer coefficient in...

B. V. Dzyubenko; G. A. Dreitser

1986-06-01T23:59:59.000Z

333

Heat transfer and hydraulic resistance of supercritical pressure coolants. Part III: Generalized description of SCP fluids normal heat transfer, empirical calculating correlations, integral method of theoretical calculations  

Science Journals Connector (OSTI)

Abstract The problems of generalized description of the supercritical-pressure fluids “normal” heat transfer are analyzed. The known empirical correlations are considered and their efficiency is assessed in view of using the refined International Standards on water and carbon dioxide thermophysical properties. The efficient methods of renovating the old correlations, as well as new correlations for calculating normal heat transfer are proposed. The modified integral method for theoretical calculating normal heat transfer is given, which makes it possible obtaining the data on the SCP flow structure.

V.A. Kurganov; Yu.A. Zeigarnik; I.V. Maslakova

2013-01-01T23:59:59.000Z

334

Molten Salt Heat Transfer Fluid (HTF)  

Energy Innovation Portal (Marketing Summaries) [EERE]

Sandia has developed a heat transfer fluid (HTF) for use at elevated temperatures that has a lower freezing point than any molten salt mixture available commercially. This allows the HTF to be used in applications in which the expensive parasitic energy costs necessary for freeze protection can be significantly reduced. The higher operating temperature limit significantly increases power cycle efficiency and overall power plan sun-to-net electric efficiency....

2013-03-12T23:59:59.000Z

335

Heat transfer to non-Newtonian power-law fluid past a continuously moving porous flat plate with heat flux  

Science Journals Connector (OSTI)

The analysis of heat transfer to the non-Newtonian power-law fluid flow past a continuously moving flat porous plate in presence of suction/injection with heat flux has been presented. We have obtained...n...=1 a...

B. P. Jadhav; B. B. Waghmode

1990-01-01T23:59:59.000Z

336

Heat Transfer Between Solids and Liquid Helium II  

Science Journals Connector (OSTI)

...February 1961 research-article Heat Transfer Between Solids and Liquid Helium...According to this author, the transfer of heat from the solid surface to the...least, some other mechanism of heat transfer may be involved. The Royal Society...

1961-01-01T23:59:59.000Z

337

The Effect of g-Jitter on Heat Transfer  

Science Journals Connector (OSTI)

...research-article The Effect of g-Jitter on Heat Transfer Norsarahaida Amin In a gravity-free...in the absence of radiation, heat transfer in a fluid medium is effected...investigation is centred upon the heat transfer from a sphere, maintained at...

1988-01-01T23:59:59.000Z

338

Heat Transfer by Radiation to Surfaces at Low Temperatures  

Science Journals Connector (OSTI)

...August 1948 research-article Heat Transfer by Radiation to Surfaces at Low...E. V. Truter A study of the transfer of heat between the walls of vacuum vessels...more efficient in diminishing the heat transfer than a highly polished surface...

1948-01-01T23:59:59.000Z

339

High flux heat transfer in a target environment  

E-Print Network [OSTI]

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

McDonald, Kirk

340

Proceeding of the 1st International Forum on Heat Transfer  

E-Print Network [OSTI]

Proceeding of the 1st International Forum on Heat Transfer November 24-26, 2004, Kyoto, Japan Paper No. HEAT TRANSFER PROBLEMS RELATED WITH CARBON NANOTUBES BY MOLECULAR DYNAMICS-BASED SIMULATIONS Dynamics Simulation, Thermal Conductance ABSTRACT Several heat transfer problems related to single

Maruyama, Shigeo

Note: This page contains sample records for the topic "flow heat transfer" 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

Heat transfer from nanoparticles: a corresponding state analysis  

E-Print Network [OSTI]

Heat transfer from nanoparticles: a corresponding state analysis Samy Merabia , Sergei Shenogin that inhibits the formation of an insulating vapor film. heat transfer | nanoparticles | liquids | phase transitions Introduction Sub-micron scale heat transfer is attracting a growing inter- est, motivated by both

Paris-Sud XI, Université de

342

STEADY STATE LIQUID CRYSTAL THERMOGRAPHY AND HEAT TRANSFER MEASUREMENTS ON  

E-Print Network [OSTI]

Chapter V STEADY STATE LIQUID CRYSTAL THERMOGRAPHY AND HEAT TRANSFER MEASUREMENTS ON SURFACES Composite Heat Transfer Surface Liquid Crystal Image Processing Technique V . 4 Experimental Results and Discussion Test Conditions and Data Analysis Application to Endwall Heat Transfer Problem Further Application

Camci, Cengiz

343

RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS  

E-Print Network [OSTI]

RADIATIVE HEAT TRANSFER WITH QUASI-MONTE CARLO METHODS A. Kersch1 W. Moroko2 A. Schuster1 1Siemens of Quasi-Monte Carlo to this problem. 1.1 Radiative Heat Transfer Reactors In the manufacturing of the problems which can be solved by such a simulation is high accuracy modeling of the radiative heat transfer

344

Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference  

E-Print Network [OSTI]

Proceedings of HT2009 2009 ASME Summer Heat Transfer Conference July 19-23, 2009, San Francisco, CA, USA HT2009-88261 SIMULATION OF FOCUSED RADIATION PROPAGATION AND TRANSIENT HEAT TRANSFER IN TURBID-dependent radiation and conduction bio-heat transfer model. Ultrashort pulsed radiation transport in the cylindrical

Guo, Zhixiong "James"

345

RECENT ADVANCES IN HEAT TRANSFER TO HELIUM 1  

E-Print Network [OSTI]

509 RECENT ADVANCES IN HEAT TRANSFER TO HELIUM 1 C. JOHANNES Service de Recherches Appliquées, L boiling, forced convection heat transfer. Relations between critical nucleate flux and some parameters confronted with the problem of calculating the heat transfer from the helium to the superconducting material

Paris-Sud XI, Université de

346

High Operating Temperature Liquid Metal Heat Transfer Fluids  

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

347

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

2011-04-14T23:59:59.000Z

348

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

349

Experimental Analysis of the Single-Phase Heat Transfer and Friction Factor inside the Horizontal Internally Micro-Fin Tube  

E-Print Network [OSTI]

and shell-side condensers to increase heat transfer. This enables water chillers to reach high efficiency, it was observed that the buoyancy effect is present in the laminar region. The efficiency index (the ratio of tube is widely used in high flow rate applications because the heat transfer enhancement in high flow

Ghajar, Afshin J.

350

Relationship between heat transfer intensity and absolute vorticity flux intensity in flat tube bank fin channels with Vortex Generators  

Science Journals Connector (OSTI)

The heat transfer enhancement can be achieved through the secondary flow. It is found that absolute vorticity flux along the main flow can describe the secondary flow intensity and correspond to the heat transfer enhancement averaged in span wise direction. Investigations to verify this phenomenon are reported. The results show that there has a similar distribution for absolute vorticity flux in the main flow direction compared with that for span averaged Nusselt number. The conformance of Nusselt number and absolute vorticity flux shows that absolute vorticity flux can reflect the intensity of heat transfer produced by the secondary flow.

Ke-Wei Song; Liang-Bi Wang

2008-01-01T23:59:59.000Z

351

Heat transfer pathways in underfloor air distribution (UFAD) systems  

E-Print Network [OSTI]

Conference of the Society of Heat- ing, Air-Conditioning,permission. QC-06-053 Heat Transfer Pathways in Underfloorthis paper: Results of heat gain shown in this theoretical

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

2006-01-01T23:59:59.000Z

352

Analysis of roll gap heat transfers in hot steel strip rolling through roll temperature sensors and heat transfer models  

E-Print Network [OSTI]

Analysis of roll gap heat transfers in hot steel strip rolling through roll temperature sensors and heat transfer models N. Legrand1,a , N. Labbe1,b D. Weisz-Patrault2,c , A. Ehrlacher2,d , T. Luks3,e heat transfers during pilot hot steel strip rolling. Two types of temperature sensors (drilled and slot

Paris-Sud XI, Université de

353

M. Bahrami ENSC 388 (F09) Steady Conduction Heat Transfer 1 Steady Heat Conduction  

E-Print Network [OSTI]

resistance of the wall. The heat transfer across the fluid/solid interface is based on Newton's law M. Bahrami ENSC 388 (F09) Steady Conduction Heat Transfer 1 Steady Heat Conduction In thermodynamics, we considered the amount of heat transfer as a system

Bahrami, Majid

354

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

E-Print Network [OSTI]

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

Maruyama, Shigeo

355

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 transfer along the tube wall of the compact heat exchanger through the use of winglets placed of attack, aspect ratio, direction, and shape, were all evaluated based on heat transfer augmentation

Thole, Karen A.

356

Journal of Enhanced Heat Transfer, 19 (5): 457476 (2012) EXPERIMENTAL INVESTIGATION OF HEAT  

E-Print Network [OSTI]

Journal of Enhanced Heat Transfer, 19 (5): 457­476 (2012) EXPERIMENTAL INVESTIGATION OF HEAT microfin tubes, most of the heat transfer and friction factor studies were focused on the turbulent region. However, there is a lack of information about the heat transfer and friction factor behavior of microfin

Ghajar, Afshin J.

357

HEAT TRANSFER ANALYSIS FOR FIXED CST AND RF COLUMNS  

SciTech Connect (OSTI)

In support of a small column ion exchange (SCIX) process for the Savannah River Site waste processing program, transient and steady state two-dimensional heat transfer models have been constructed for columns loaded with cesium-saturated crystalline silicotitanate (CST) or spherical Resorcinol-Formaldehyde (RF) beads and 6 molar sodium tank waste supernate. Radiolytic decay of sorbed cesium results in heat generation within the columns. The models consider conductive heat transfer only with no convective cooling and no process flow within the columns (assumed column geometry: 27.375 in ID with a 6.625 in OD center-line cooling pipe). Heat transfer at the column walls was assumed to occur by natural convection cooling with 35 C air. A number of modeling calculations were performed using this computational heat transfer approach. Minimal additional calculations were also conducted to predict temperature increases expected for salt solution processed through columns of various heights at the slowest expected operational flow rate of 5 gpm. Results for the bounding model with no process flow and no active cooling indicate that the time required to reach the boiling point of {approx}130 C for a CST-salt solution mixture containing 257 Ci/liter of Cs-137 heat source (maximum expected loading for SCIX applications) at 35 C initial temperature is about 6 days. Modeling results for a column actively cooled with external wall jackets and the internal coolant pipe (inlet coolant water temperature: 25 C) indicate that the CST column can be maintained non-boiling under these conditions indefinitely. The results also show that the maximum temperature of an RF-salt solution column containing 133 Ci/liter of Cs-137 (maximum expected loading) will never reach boiling under any conditions (maximum predicted temperature without cooling: 88 C). The results indicate that a 6-in cooling pipe at the center of the column provides the most effective cooling mechanism for reducing the maximum temperature with either ion exchange material. Sensitivity calculations for the RF resin porosity, the ambient external column temperature, and the cooling system configuration were performed under the baseline conditions to assess the impact of these parameters on the maximum temperatures. It is noted that the cooling mechanism at the column boundary (forced versus natural convection) and the cooling system configuration significantly impact the maximum temperatures. The analysis results provide quantitative information associated with process temperature control requirements and management of the SCIX column.

Lee, S

2007-10-17T23:59:59.000Z

358

Heat transfer to a horizontal cylinder in a shallow bubble column  

Science Journals Connector (OSTI)

Abstract Heat transfer coefficient correlations for tall bubble columns are unable to predict heat transfer in shallow bubble columns, which have unique geometry and fluid dynamics. In this work, the heat transfer coefficient is measured on the surface of a horizontal cylinder immersed in a shallow air–water bubble column. Superficial velocity, liquid depth, and cylinder height and horizontal position with respect to the sparger orifices are varied. The heat transfer coefficient is found to increase with height until reaching a critical height, and a dimensionless, semi-theoretical correlation is developed that incorporates superficial velocity, liquid properties, and height. Additionally, the more minor effects of flow regime, column region, and bubble impact are discussed. Notably, the heat transfer coefficient can be as high in the region of bubble coalescence as in the bulk of the column, but only if bubbles impact the cylinder. The correlation and discussion provide a framework for modeling and designing shallow, coil-cooled bubble columns.

Emily W. Tow; John H. Lienhard V

2014-01-01T23:59:59.000Z

359

Heat Transfer Study of Polymer Solutions with Different Rigidities  

E-Print Network [OSTI]

considered for flow and heat transfer simulations. A number of studies, both experimental and theoretical, have been performed using viscosity models for non-Newtonian fluids. O. Waele [5] first introduced the power law model for time-independent non..., the fourth part focuses on the effect of the polymer rigidity on the dynamic viscosity. 2.1 Viscosity Model of Non-Newtonian Fluid Numerous studies have been done on the prediction of the viscosity models of non- Newtonian fluids. Waele [5] introduced...

Huang, Yao

2014-05-08T23:59:59.000Z

360

Summary Weusedthreemethodstomeasureboundarylayer conductance to heat transfer (gbH) and water vapor transfer  

E-Print Network [OSTI]

Summary Weusedthreemethodstomeasureboundarylayer conductance to heat transfer (gbH) and water vapor of transpiration). The boundary layer conductance to heat transfer is small enough that leaf temperature can become diffusion, the boundary layer around a leaf also provides resistance to the transfer of heat between a leaf

Martin, Timothy

Note: This page contains sample records for the topic "flow heat transfer" 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

RADIATIVE HEAT TRANSFER WITH QUASIMONTE CARLO METHODS \\Lambda  

E-Print Network [OSTI]

RADIATIVE HEAT TRANSFER WITH QUASI­MONTE CARLO METHODS \\Lambda A. Kersch 1 W. Morokoff 2 A accuracy modeling of the radiative heat transfer from the heater to the wafer. Figure 1 shows the draft Carlo simulation is often used to solve radiative transfer problems where complex physical phenomena

362

CONDUCTION HEAT TRANSFER Dr. Ruhul Amin Fall 2011  

E-Print Network [OSTI]

ME 525 CONDUCTION HEAT TRANSFER Dr. Ruhul Amin Fall 2011 Office: 201C Roberts Hall Lecture Room of conduction heat transfer. Important results which are useful for engineering application will also: 121 Roberts Hall Phone: 994-6295 Lecture Periods: 12:45- 2:00, TR TEXT: Heat Conduction, M. N. Ozisik

Dyer, Bill

363

Jet impingement heat transfer in two-pass rotating rectangular channels  

E-Print Network [OSTI]

compared with previously reported correlations. The pressure distributions show that the major effect on heat transfer is the jet impingement in the beginning of the channel and the cross flow at the end of the channel. The results also show that heat...

Zhang, Yuming

2012-06-07T23:59:59.000Z

364

A Study of Heat Transfer in a Composite Wall Collector System with Porous Absorber  

E-Print Network [OSTI]

In this paper, heat transfer and flow in a composite solar wall with porous absorber has been studied. The unsteady numerical simulation is employed to analyze the performance of the flow and temperature field in the composite solar wall. The excess...

Chen, W.

2006-01-01T23:59:59.000Z

365

Effect of flow and physical parameters on the wax deposition of Middle East crude oil under subsea condition: heat transfer viewpoint  

Science Journals Connector (OSTI)

Change in pressure, temperature, flow rate and concentration of oil causes precipitation and deposition of wax particles in the pipelines which has become a major problem for ... reserves increases. Change in tem...

Reza Gooya; Mehdy Gooya; Bahram Dabir

2013-08-01T23:59:59.000Z

366

Radiative heat transfer in 2D Dirac materials  

E-Print Network [OSTI]

We compute the radiative heat transfer between two sheets of 2D Dirac materials, including topological Chern insulators and graphene. Neglecting spatial dispersion, we derive both numerically and analytically the short-distance asymptotics of the near-field heat transfer in these systems, and show that it scales as the inverse of the distance between the two sheets. We argue that this scaling law for the near-field heat transfer is generic for any two-dimensional systems.

Pablo Rodriguez-Lopez; Wang-Kong Tse; Diego A. R. Dalvit

2014-10-16T23:59:59.000Z

367

Sensitivity Analysis of the Gap Heat Transfer Model in BISON.  

SciTech Connect (OSTI)

This report summarizes the result of a NEAMS project focused on sensitivity analysis of the heat transfer model in the gap between the fuel rod and the cladding used in the BISON fuel performance code of Idaho National Laboratory. Using the gap heat transfer models in BISON, the sensitivity of the modeling parameters and the associated responses is investigated. The study results in a quantitative assessment of the role of various parameters in the analysis of gap heat transfer in nuclear fuel.

Swiler, Laura Painton; Schmidt, Rodney C.; Williamson, Richard (INL); Perez, Danielle (INL)

2014-10-01T23:59:59.000Z

368

The heat transfer coefficients of the heating surface of 300 MWe CFB boiler  

Science Journals Connector (OSTI)

A study of the heat transfer about the heating surface of three commercial 300 MWe CFB boilers was conducted in this work. The ... heat balance of the hot circuit of the CFB boiler. With the boiler capacity incre...

Haibo Wu; Man Zhang; Qinggang Lu; Yunkai Sun

2012-08-01T23:59:59.000Z

369

Submersible pumping system with heat transfer mechanism  

DOE Patents [OSTI]

A submersible pumping system for downhole use in extracting fluids containing hydrocarbons from a well. In one embodiment, the pumping system comprises a rotary induction motor, a motor casing, one or more pump stages, and a cooling system. The rotary induction motor rotates a shaft about a longitudinal axis of rotation. The motor casing houses the rotary induction motor such that the rotary induction motor is held in fluid isolation from the fluid being extracted. The pump stages are attached to the shaft outside of the motor casing, and are configured to impart fluid being extracted from the well with an increased pressure. The cooling system is disposed at least partially within the motor casing, and transfers heat generated by operation of the rotary induction motor out of the motor casing.

Hunt, Daniel Francis Alan; Prenger, F. Coyne; Hill, Dallas D; Jankowski, Todd Andrew

2014-04-15T23:59:59.000Z

370

An evaluation of heat flow transducers as a means of determining soil heat flow  

E-Print Network [OSTI]

provided to the Micrometeorology Section, Department of Oceanography and Meteorology, ARM College of Texas by the Signal Corps of the United States Army, under Contract No. DA 36-039 AMC-02195 (E). The heat flow plates used in this study were provided... surface soil heat flow. The results show that acceptable performance of the plates in the measurement of heat flow is possible although in general should not be expected without thorough testing, and even then there are restrictive considerations...

King, Barney L. D

2012-06-07T23:59:59.000Z

371

Transient heat transfer properties in a pulse detonation combustor .  

E-Print Network [OSTI]

??The heat transfer along the axis of a pulse detonation combustor has been characterized for various frequencies and fill fractions at 2.5 atmospheres of pressure… (more)

Fontenot, Dion G.

2011-01-01T23:59:59.000Z

372

Experimental Measurement of Radiation Heat Transfer from Complex Fenestration Systems.  

E-Print Network [OSTI]

??A well instrumented facility for the measurement of heat transfer from complex fenestration systems was built and validated. The facility provided very accurate measurements based… (more)

Wilson, Barry Allan

2007-01-01T23:59:59.000Z

373

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

374

Integrated-optic fluid sensor using heat transfer  

Science Journals Connector (OSTI)

An integrated-optic fluid sensor utilizing the heat-transfer phenomenon is proposed. An optical waveguide interferometer is used to convert the temperature of the waveguide surface...

Enokihara, Akira; Izutsu, Masayuki; Sueta, Tadasi

1988-01-01T23:59:59.000Z

375

Characterization and Development of Advanced Heat Transfer Technologies (Presentation)  

SciTech Connect (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

376

A Method for Improving Heat Transfer to a Cryogenic Fluid  

Science Journals Connector (OSTI)

Since 1934, when Nukiyama [1] carried out his classic experiment with a heated platinum wire in water at 100°C, the phenomena associated with boiling heat transfer have received an ever increasing amount of at...

C. W. Cowley; W. J. Timson; J. A. Sawdye

1962-01-01T23:59:59.000Z

377

6th International Symposium on Multiphase Flow, Heat Mass Transfer and Energy Conversion ISMF2009, Xi'an, China, 11-15 July 2009  

E-Print Network [OSTI]

the case with materials of high thermal conductivity subjected to natural convection. To increase the heat is low. It is possible to appreciably enhance the performance of low thermal conductivity material. It also predicts based on computational simulation that the decrease in internal thermal resistance

Khandekar, Sameer

378

The influence of multiple tubes on the tube-to-bed heat transfer in a fluidised bed L.M. Armstrong, S. Gu  

E-Print Network [OSTI]

for flow prediction in the past without heat transfer modelling. In the present study, a two-fluid EulerianThe influence of multiple tubes on the tube-to-bed heat transfer in a fluidised bed L.M. Armstrong Keywords: CFD Heat transfer Fluidised bed Eulerian a b s t r a c t There have been few studies modelling

379

Proceedings of HT'03 2003 Summer Heat Transfer Conference  

E-Print Network [OSTI]

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

Walker, D. Greg

380

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

E-Print Network [OSTI]

creating unique visual and quantitative data. These data were then analyzed using a resistance type heat transfer model and five different zero gravity flow regime maps. Results from this analysis included: (i) presenting zero gravity data that correlated...

Westheimer, David Thomas

2012-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

E-Print Network 3.0 - advanced heat transfer Sample Search Results  

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

Performance Evaluations Alternate... and Diagnostic Center (EADC) Ground Coupled Heat Pumps Heat and Mass Transfer in Attic Systems Industrial... and Heat Transfer...

382

Heat and moisture transfer through clothing for a person with contact surface  

E-Print Network [OSTI]

S, Kornadt O et al (2009) Heat and moisture transfer throughTopic A7: Thermal comfort Heat and moisture transfer throughClothing, Modelling, Heat transfer, Moisture transfer,

Fu, Ming; Yu, Tiefeng; Zhang, Hui; Weng, Wenguo; Yuan, Hongyong

2014-01-01T23:59:59.000Z

383

Proceedings of the 29th National Heat Transfer Conference of Italy, Politecnico di Torino, Torino, Italy, June 2022, 2011 INTRODUCTION  

E-Print Network [OSTI]

trends are known, no information about the local heat transfer coefficient in the evaporator U.D.) has been brazed on the main tube of the condenser section in order to connect the vacuum/filling valve transducer 20 Copper fitting FLOW PATTERNS AND CORRESPONDING LOCAL HEAT TRANSFER COEFFICIENTS IN A PULSATING

Khandekar, Sameer

384

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

385

Heat Transfer across the Interface between Nanoscale Solids and Gas  

Science Journals Connector (OSTI)

(4-7) Relative to heat transferred via solid–solid interfaces, heat dissipation from the active device region to the gas environment is usually negligible. ... Long VO2 NWs were cantilevered from a substrate and were locally heated using a focused laser, allowing the laser-heating induced phase transition and the resultant domain structures along the NW to be optically imaged. ... By imaging the laser-heating induced metal–insulator phase transition along single, free-standing VO2 NWs, we determined the heat transfer coefficient between the NW and the gas environment over a wide range of pressure and down to the submicrometer scale. ...

Chun Cheng; Wen Fan; Jinbo Cao; Sang-Gil Ryu; Jie Ji; Costas P. Grigoropoulos; Junqiao Wu

2011-11-09T23:59:59.000Z

386

Heat transfer in proteinwater interfaces Anders Lervik,ab  

E-Print Network [OSTI]

Heat transfer in protein­water interfaces Anders Lervik,ab Fernando Bresme,*ac Signe Kjelstrup of the heat diffusion equation we compute the thermal conductivity and thermal diffusivity of the proteins by about 4 nm.4 It is expected that the energy transfer between these sites may involve the concerted

Kjelstrup, Signe

387

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

388

Performance of a pressure-based unstructured code and a multi-block structured code for heat transfer and fluid flow  

Science Journals Connector (OSTI)

This paper reports a multi-block unstructured method for incompressible flows and the performance comparison with a multi-block structured method. The unstructured collocated grid is composed of arbitrary cell shapes. Pressure and velocity are stored at cell centres; Rhie and Chow interpolation is used to prevent checker boarding. The SIMPLE algorithm is used for pressureâ??velocity coupling. The code is calibrated with benchmark cases using hexahedral and prism meshes, and is shown to perform very well for all cases considered. In addition, the performances of the structured and unstructured codes are compared.

Rongguang Jia; Bengt Sunden

2005-01-01T23:59:59.000Z

389

Establishment of a research facility for investigating the effects of unsteady inlet flow, pressure gradient and curvature on boundary layer development, wake development and heat transfer  

E-Print Network [OSTI]

2. LITERATURE REVIEW 3. OBJECTIVES TABLE OF CONTENTS Page nl tv v111 xt 4. THE EXPERIMENTAL TEST FACILITY 4. 1. Overall Layout of the Test Facility 4, 2. The Fan and Inlet Duct Assembly 4. 3. The Diffuser, Settling Chamber and Nozzle... Assembly . 4. 4. The Wake Generator to Simulate Unsteady Inlet Flow . 4, 5. The Test Section to Simulate Blade Curvature 4, 6, The Convex Wall and Traversing System 4. 7, Adjustment of the Turbulence Level 4. 8. Capabilities of the Test Facility, 5...

Pardivala, Darayus Noshir

2012-06-07T23:59:59.000Z

390

Heat Transfer from Rotating Blade Platforms with and without Film Cooling  

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

Transfer from Rotating Blade Transfer from Rotating Blade Platforms with and without Film Cooling J.C. Han and M.T. Schobeiri SCIES Project 03-01-SR113 DOE COOPERATIVE AGREEMENT DE-FC26-02NT41431 Texas A&M University Tom J. George, Program Manager, DOE/NETL Richard Wenglarz, Manager of Research, SCIES Project Awarded 07/01/2003 (36 Month Duration) $461,024 Total Contract Value ($361,024 DOE) Turbine Heat Transfer Laboratory Texas A&M University SR 113 - 10-2005 - JCHan Gas Turbine Needs Need Detailed Heat Transfer Data on Rotating Blade Platforms Improve Current Rotor Blade Cooling Schemes Provide Options for New Rotor Blade Cooling Designs Need Accurate and Efficient CFD Codes to Improve Flow and Heat Transfer Predictions and Guide Rotor Blade Cooling Designs Improved Turbine Power Efficiency by Increasing Turbine

391

Influence of circumferential solar heat flux distribution on the heat transfer coefficients of linear Fresnel collector absorber tubes  

Science Journals Connector (OSTI)

Abstract The absorber tubes of solar thermal collectors have enormous influence on the performance of the solar collector systems. In this numerical study, the influence of circumferential uniform and non-uniform solar heat flux distributions on the internal and overall heat transfer coefficients of the absorber tubes of a linear Fresnel solar collector was investigated. A 3D steady-state numerical simulation was implemented based on ANSYS Fluent code version 14. The non-uniform solar heat flux distribution was modelled as a sinusoidal function of the concentrated solar heat flux incident on the circumference of the absorber tube. The k–? model was employed to simulate the turbulent flow of the heat transfer fluid through the absorber tube. The tube-wall heat conduction and the convective and irradiative heat losses to the surroundings were also considered in the model. The average internal and overall heat transfer coefficients were determined for the sinusoidal circumferential non-uniform heat flux distribution span of 160°, 180°, 200° and 240°, and the 360° span of circumferential uniform heat flux for 10 m long absorber tubes of different inner diameters and wall thicknesses with thermal conductivity of 16.27 W/mK between the Reynolds number range of 4000 and 210,000 based on the inlet temperature. The results showed that the average internal heat transfer coefficients for the 360° span of circumferential uniform heat flux with different concentration ratios on absorber tubes of the same inner diameters, wall thicknesses and thermal conductivity were approximately the same, but the average overall heat transfer coefficient increased with the increase in the concentration ratios of the uniform heat flux incident on the tubes. Also, the average internal heat transfer coefficient for the absorber tube with a 360° span of uniform heat flux was approximately the same as that of the absorber tubes with the sinusoidal circumferential non-uniform heat flux span of 160°, 180°, 200° and 240° for the heat flux of the same concentration ratio, but the average overall heat transfer coefficient for the uniform heat flux case was higher than that of the non-uniform flux distributions. The average axial local internal heat transfer coefficient for the 360° span of uniform heat flux distribution on a 10 m long absorber tube was slightly higher than that of the 160°, 200° and 240° span of non-uniform flux distributions at the Reynolds number of 4 000. The average internal and overall heat transfer coefficients for four absorber tubes of different inner diameters and wall thicknesses and thermal conductivity of 16.27 W/mK with 200° span of circumferential non-uniform flux were found to increase with the decrease in the inner-wall diameter of the absorber tubes. The numerical results showed good agreement with the Nusselt number experimental correlations for fully developed turbulent flow available in the literature.

Izuchukwu F. Okafor; Jaco Dirker; Josua P. Meyer

2014-01-01T23:59:59.000Z

392

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

393

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...

Su, J.; Li, J.

2006-01-01T23:59:59.000Z

394

The Advantages of Sealless Pumps in Heat Transfer Fluid Services  

E-Print Network [OSTI]

THE ADV ANTAGES OF SEALLESS PUMPS IN HEAT TRANSFER FLUID SERVICES Michael D. Smith Engineering Manager Sundstrand Fluid Handling Arvada, CO ABSTRACT The expectations for heat transfer fluid (HTF) system safety and reliability... of the issues which challenge mechanical seals. In addition, one type of sealless pump, the canned motor pump, raises the thermal efficiency of HTF systems. Waste heat from the drive motors of m'ost pumps is dissipated to the air. A shaft driven fan wastes...

Smith, M. D.

395

Numerical simulation of heat transfer performance of an air-cooled steam condenser in a thermal power plant  

Science Journals Connector (OSTI)

Numerical simulation of the thermal-flow characteristics and heat transfer performance is made of an air-cooled steam condenser (ACSC) in a thermal power plant by considering the effects of ambient wind speed and...

Xiufeng Gao; Chengwei Zhang; Jinjia Wei; Bo Yu

2009-09-01T23:59:59.000Z

396

On free convection heat transfer with well defined boundary conditions  

SciTech Connect (OSTI)

The scaling of free convection heat transfer is investigated. The non-dimensional groups for Boussinesq and fully compressible variable property free convection, driven by isothermal surfaces, are derived using a previously published novel method of dimensional analysis. Both flows are described by a different set of groups. The applicability of each flow description is experimentally investigated for the case of the isothermal horizontal cylinder in an air-filled isothermal enclosure. The approach taken to the boundary conditions differs from that of previous investigations. Here, it is argued that the best definition of the boundary conditions is achieved for heat exchange between the cylinder and the enclosure rather than the cylinder and an arbitrarily chosen fluid region. The enclosure temperature is shown both analytically and experimentally to affect the Nusselt number. The previously published view that the Boussinesq approximation has only a limited range of application is confirmed, and the groups derived for variable property compressible free convection are demonstrated to be correct experimentally. A new correlation for horizontal cylinder Nusselt number prediction is presented.

Davies, M.R.D.; Newport, D.T.; Dalton, T.M.

1999-07-01T23:59:59.000Z

397

NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED BUILDING ENERGY AND CFD SIMULATION  

E-Print Network [OSTI]

for the correct prediction of the convective heat. A finer grid resolution in CFD does not always lead to a more conservation equations of flow on these grid cells. As shown in Figure 1(a), CFD calculates convective heat1 NUMERICAL DETERMINATION AND TREATMENT OF CONVECTIVE HEAT TRANSFER COEFFICIENT IN THE COUPLED

Chen, Qingyan "Yan"

398

Analysis of conjugate heat transfer in tube-in-block heat exchangers for some engineering applications.  

E-Print Network [OSTI]

??This project studied the effect of different parameters on the conjugate heat transfer in tube-in-block heat exchangers for various engineering applications. These included magnetic coolers… (more)

Gari, Abdullatif Abdulhadi

2006-01-01T23:59:59.000Z

399

Heat Transfer of Heat-Releasing Fluid in the Top Portion of a Closed Volume  

Science Journals Connector (OSTI)

The method of analytic estimates is used to determine the characteristics of steady-state free-convection heat transfer of a fluid with internal heat sources in the top part of a closed volume with different cond...

D. G. Grigoruk; P. S. Kondratenko

2004-03-01T23:59:59.000Z

400

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...

Gaskill, Travis

2012-02-14T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

Study of natural convection heat transfer above a horizontal heated plate using a laser specklegram technique  

E-Print Network [OSTI]

Heat transfer by free convection in air from an isothermal horizontal heated flat plate facing upward has been experimentally studied by using a non intrusive and accurate optical technique, Speckle photography or a specklegram technique. The local...

Cheeti, Satish K.R.

2012-06-07T23:59:59.000Z

402

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

403

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

E-Print Network [OSTI]

tJ ,.I and the fluid heat transfer characteristics. As [13]Introduction Most fluid flows and heat transfer processes ofproportion of fluid dynamic and heat transfer researchers

Samaraweera, D.S.A.

2011-01-01T23:59:59.000Z

404

Heat-Traced Fluid Transfer Lines  

E-Print Network [OSTI]

This paper discusses basic considerations in designing a heat tracing system using either team or electrical tracing. Four basic reasons to heat trace are dealt with: water freeze protection, chemical freeze protection, viscosity maintenance...

Schilling, R. E.

1984-01-01T23:59:59.000Z

405

Joule heating and heat transfer in poly(dimethylsiloxane) microfluidic systems  

E-Print Network [OSTI]

Joule heating and heat transfer in poly(dimethylsiloxane) microfluidic systems David Erickson microfluidic/biochip systems must have the ability to rapidly reject this heat to the surroundings. Generally it is the ability to dissipate this heat that limits the strength of the applied electric field and thus the maximum

Erickson, David

406

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...

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

2006-01-01T23:59:59.000Z

407

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

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

408

AndreiG.Fedorov Title: George W. Woodruff Professorship in Heat Transfer, Combustion and  

E-Print Network [OSTI]

AndreiG.Fedorov Title: George W. Woodruff Professorship in Heat Transfer, Combustion and Energy Research Areas of Interest Heat Transfer, combustion, and energy systems Bioengineering, lab ionization and imaging for bioanalytical mass spectrometry Thermal radiation heat transfer Thermal

Garmestani, Hamid

409

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

410

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

411

Mathematical circulation model for the blood-flow-heat-loss relationship in the rat tail  

Science Journals Connector (OSTI)

A mathematical model for the heat-loss-blood-flow relationship is developed for the rat tail. When supplied with experimental values of heat loss and blood flow, the model allows one to compute the distribution of flow in deep and cutaneous vessels as a function of body core and tail temperature and to determine the savings in heat loss that result from alterations in the pattern of circulation and from counter-current heat transfer. Blood flow in the cutaneous and deep lying veins of the tail is controlled by both central and local temperatures and increases fairly linearly with deep body temperature. However, the distribution of blood flow in the tail is controlled only by local tail temperature and is independent of deep body temperature. The change in venous distribution of flow has a great impact on the conservation of heat and can reduce the heat loss from the circulating blood by more than 50% when venous return is directed to deep lying veins. On the other hand, counter-current heat transfer is of only minor importance in the control of heat loss from the tail, resulting at most in a 10% saving of heat loss, and that only at the smallest rate of blood flow.

E R Raman; V J Vanhuyse; M F Roberts

1987-01-01T23:59:59.000Z

412

A model of heat and moisture transfer through clothing integrated with the UC Berkeley comfort model  

E-Print Network [OSTI]

M. Convective and radiative heat transfer coefficients forH, Katayama T. Convective heat transfer coefficients andequations, and the heat transfer effects of different

Fu, Ming; Yu, Tiefeng; Zhang, Hui; Arens, Edward; Weng, Wenguo; Yuan, Hongyong

2014-01-01T23:59:59.000Z

413

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

414

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

E-Print Network [OSTI]

rates of rocks- to-fluid heat transfer, and thereby thesurface for heat transfer to injected fluids circulating influids, and thereby increase the overall rate of heat transfer

Pruess, K.

2011-01-01T23:59:59.000Z

415

Experimental and numerical study of pressure drop and heat transfer in a single-phase micro-channel heat sink  

E-Print Network [OSTI]

Experimental and numerical study of pressure drop and heat transfer in a single-phase micro Received 6 July 2001; received in revised form 26 October 2001 Abstract The pressure drop and heat transfer-dimensional heat transfer characteristics of the heat sink were analyzed numerically by solving the conjugate heat

Qu, Weilin

416

Seasonal thermal signatures of heat transfer by water exchange in an underground vault  

Science Journals Connector (OSTI)

......such a cavity, water phases do not need...place, and vertical water flow can be small...Aburatsubo, with a recovery time larger than...heat transfer by water exchange. This...evaporation and condensation process. If the...Monitoring the atmospheric temperature in a......

Frédéric Perrier; Pierre Morat; Toshio Yoshino; Osam Sano; Hisashi Utada; Olivier Gensane; Jean-Louis Le Mouël

2004-07-01T23:59:59.000Z

417

International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics 14 16 July 2014  

E-Print Network [OSTI]

such as reduction of paraffin wax deposition in petroleum transport lines, air lift system, solar collectors ­ 16 July 2014 Orlando, Florida NON-BOILING HEAT TRANSFER IN HORIZONTALAND NEAR HORIZONTAL DOWNWARD, majority of the research in this field have been conducted for two phase flow in horizontal and vertical

Ghajar, Afshin J.

418

MODELLING OF TRANSPORT PHENOMENA FOR THE HYPERSONIC STAGNATION POINT HEAT TRANSFER PROBLEM  

E-Print Network [OSTI]

MODELLING OF TRANSPORT PHENOMENA FOR THE HYPERSONIC STAGNATION POINT HEAT TRANSFER PROBLEM A to vibrational mode el refers to electronic mode Introduction One of the major problems encountered in hypersonic. The hypersonic flow about such surfaces is charac­ terized by a strong bow shock, which converts the major part

419

Experimental investigations of uncovered-bundle heat transfer and two-phase mixture-level swell under high-pressure low heat-flux conditions. [PWR  

SciTech Connect (OSTI)

Results are reported from a series of uncovered-bundle heat transfer and mixture-level swell tests. Experimental testing was performed at Oak Ridge National Laboratory in the Thermal Hydraulic Test Facility (THTF). The THTF is an electrically heated bundle test loop configured to produce conditions similar to those in a small-break loss-of-coolant accident. The objective of heat transfer testing was to acquire heat transfer coefficients and fluid conditions in a partially uncovered bundle. Testing was performed in a quasi-steady-state mode with the heated core 30 to 40% uncovered. Linear heat rates varied from 0.32 to 2.22 kW/m.rod (0.1 to 0.68 kW/ft.rod). Under these conditions peak clad temperatures in excess of 1050 K (1430/sup 0/F) were observed, and total heat transfer coefficients ranged from 0.0045 to 0.037 W/cm/sup 2/.K (8 to 65 Btu/h.ft/sup 2/./sup 0/F). Spacer grids were observed to enhance heat transfer at, and downstream of, the grid. Radiation heat transfer was calculated to account for as much as 65% of total heat transfer in low-flow tests.

Anklam, T. M.; Miller, R. J.; White, M. D.

1982-03-01T23:59:59.000Z

420

Triaxial thermopile array geo-heat-flow sensor  

DOE Patents [OSTI]

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

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

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "flow heat transfer" 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

Triaxial thermopile array geo-heat-flow sensor  

DOE Patents [OSTI]

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

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

1992-01-01T23:59:59.000Z

422

Khounsary Named Associate Editor of ASME Journal of Heat Transfer  

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

423

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

424

Enhancement of Pool Boiling Heat Transfer in Confined Space  

E-Print Network [OSTI]

Pool boiling is an effective method used in many technical applications for a long time. Its highly efficient heat transfer performance results from not only the convection effect but also the phase change process in pool boiling. Pool boiling...

Hsu, Chia-Hsiang

2014-05-05T23:59:59.000Z

425

Heat transfer in open cell polyurethane foam insulation  

Science Journals Connector (OSTI)

This paper study systematic investigates the combined conductive and non-gray radiative heat transfer of open cell polyurethane (PU) foam in the pressure range between 760 and 0.02?Torr. Direct transmission m...

J.-W. Wu; H.-S. Chu

1998-11-01T23:59:59.000Z

426

Heat transfer between anisotropic nanopartricles: Enhancement and switching  

E-Print Network [OSTI]

We theoretically study heat transfer between two anisotropic nanoparticles in vacuum, and derive closed expressions in terms of the anisotropic dipole polarizabilities. We show that transfer between two small spheroids can be many times as large as the one for two spheres of same volumes. Such increase with anisotropy is also found for the heat emission of an isolated small spheroid. Furthermore, we observe a strong dependence of transfer on the relative orientation, yielding the interpretation as a heat transfer switch. The switch quality, given as the ratio of transfer in the ``on'' and ``off'' positions, is observed to be as large as $10^3$ in the near field and even larger in the far field.

Roberta Incardone; Thorsten Emig; Matthias Krüger

2014-02-21T23:59:59.000Z

427

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

E-Print Network [OSTI]

across vertical fluid layers, Journal of Heat Transfer.fluid dynamics and conduction simulations of heat transferheat transfer through such window frames, we need, ideally, to simulate fluid

Gustavsen, Arild

2009-01-01T23:59:59.000Z

428

Using Solid Particles as Heat Transfer Fluid for use in Concentrating...  

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

Using Solid Particles as Heat Transfer Fluid for use in Concentrating Solar Power (CSP) Plants Using Solid Particles as Heat Transfer Fluid for use in Concentrating Solar Power...

429

Heat transfer efficiency of biomass cookstoves.  

E-Print Network [OSTI]

??Nearly half of the world’s human population burns biomass fuel to meet home energy needs for heating and cooking. Biomass combustion often releases harmful chemical… (more)

Zube, Daniel Joseph

2010-01-01T23:59:59.000Z

430

Plume heat flow is much lower than CMB heat flow Eric Mittelstaedt a,*, Paul J. Tackley a,b  

E-Print Network [OSTI]

to follow a power-law size distribution, estimated a plume heat flux as high as 35% of surface heat fluxPlume heat flow is much lower than CMB heat flow Eric Mittelstaedt a,*, Paul J. Tackley a, of the heat conducted across the CMB. Here this assumption is explored using numerical convection models

Tackley, Paul J.

431

Heat transfer enhancement resulting from induction electrohydrodynamic pumping  

E-Print Network [OSTI]

HEAT TRANSFER ENHANCEMENT RESULTING FROM INDUCTION ELECTROHYDRODYNAMIC PUMPING A Thesis by BRYAN DAVID MARGO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 1992 Major Subject: Mechanical Engineering HEAT TRANSFER ENHANCEMENT RESULTING FROM INDUCTION ELECTROHYDRODYNAMIC PUMPING A Thesis by BRYAN DAVID MARGO Approved as to style and content by: Jamal Seyed- Yagoobi (Chair...

Margo, Bryan David

1992-01-01T23:59:59.000Z

432

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

E-Print Network [OSTI]

to minimize the effects of the temperature. Chandrupatla and Sastri (1977) used a finite difference method to study laminar heat transfer and fluid flow for Non-Newtonian fluids. In the limiting case of Newtonian fluids their results showed good agreement... and Sastri (1977) for developing laminar flow in a rectangular smooth channel. Figure 4. 1 shows the numerically predicted centerline axial velocity compared with the experimental data of Goldstein and Kreid (1967). The agreement between the numerical...

Lopez Buso, Jorge Ricardo

2012-06-07T23:59:59.000Z

433

Heat Transfer Research 44(1), 130 (2013) ENTROPY GENERATION ANALYSIS  

E-Print Network [OSTI]

Heat Transfer Research 44(1), 1­30 (2013) ENTROPY GENERATION ANALYSIS FOR A PULSATING HEAT­vapor phase 2 Kim, Zhang, & Choi Heat Transfer Research NOMENCLATURE A area, m2 Qin,s,l sensible heat transfer into cp specific heat at constant liquid slug, W pressure, Qout,s,l sensible heat transfer out cv specific

Zhang, Yuwen

434

Literature survey of heat transfer enhancement techniques in refrigeration applications  

SciTech Connect (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

435

Interpretive geothermal heat flow map of Colorado | Open Energy...  

Open Energy Info (EERE)

Interpretive geothermal heat flow map of Colorado Jump to: navigation, search OpenEI Reference LibraryAdd to library Map: Interpretive geothermal heat flow map of ColoradoInfo...

436

Investigation of Heat Transfer and Combustion in the Advanced Fluidized Bed Combustor (FBC).  

SciTech Connect (OSTI)

This technical report summarizes the research conducted and progress achieved during the period from April 1, 1997 to June 30, 1997. The exploratory hot model was modified to explore the operational limits, fuel flexibility, and the role of heat transfer in combustion control. Eight air injection nozzles were newly designed to set different angles. Three runs of independently controllable water-cooling tubes were arranged to study the local heat transfer characteristics along the flow direction of the combustor height. The fuel nozzle was carefully designed to improve the fuel atomization quality. The igniter system was designed to safe and dependable ignition. According to the established safety and health guideline, the auxiliary subsystems are inspected carefully. All instruments are checked and calibrated for the system test. The combustion test result was analyzed to understand thermal performance and heat transfer characteristics. The flame enthalpy decreased along the combustor height. The heat is removed by the cooling water at different zones during the combustion test. The axial variation of heat transfer coefficient was predicted. The heat transfer coefficient is generally lower in the top area than in the bottom of the combustor.

Lee, S.W.

1997-07-01T23:59:59.000Z

437

AIAA Journal of Thermophysics and Heat Transfer Vol. 13(1), pp. 126-133, 1999  

E-Print Network [OSTI]

= specific heat, W kg-1 k-1 h = heat transfer coefficient of evaporator, W m-2 K-1 hfg = latent heat of fluid1 AIAA Journal of Thermophysics and Heat Transfer Vol. 13(1), pp. 126-133, 1999 Evaporative Heat Transfer in a Capillary Structure Heated by a Grooved Block Q. Liao* and T. S. Zhao The Hong Kong

Zhao, Tianshou

438

Heat Flow in the Hungarian Basin  

Science Journals Connector (OSTI)

... the basin is deep and the gradient is between 40 and 45 C/km. This geothermal low may be characterized by 1-4-1-6 [jical/cm2 sec except if ... is about 1*5 sec can bo considered as the Western boundary of the Hungarian geothermal anomaly, since heat flow diminishes from that line in the north-west direction to ...

T. BOLDIZSÁR

1964-06-27T23:59:59.000Z

439

Radio frequency (RF) heated supersonic flow laboratory  

SciTech Connect (OSTI)

A unique supersonic flow apparatus which employs an inductively-coupled, radio frequency (RF) torch to supply high enthalpy source gas to the nozzle inlet is described. The main features of this system are the plasma tube, a cooled nozzle assembly, and a combustion/expansion chamber with a heat exchanger. A description of these components with current test data is presented. In addition, a discussion of anticipated experiments utilizing this system is included.

Wantuck, P.; Watanabe, H.

1990-01-01T23:59:59.000Z

440

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

Note: This page contains sample records for the topic "flow heat transfer" 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

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

442

Heat transfer in a thermoelectric generator for diesel engines  

SciTech Connect (OSTI)

This paper discusses the design and test results obtained for a 1kW thermoelectric generator used to convert the waste thermal energy in the exhaust of a Diesel engine directly to electric energy. The paper focuses on the heat transfer within the generator and shows what had to be done to overcome the heat transfer problems encountered in the initial generator testing to achieve the output goal of 1kW electrical. The 1kW generator uses Bismuth-Telluride thermoelectric modules for the energy conversion process. These modules are also being evaluated for other waste heat applications. Some of these applications are briefly addressed.

Bass, J.C. [Hi-Z Technology, Inc., San Diego, CA (United States)

1995-12-31T23:59:59.000Z

443

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...

Chen, Y.; Zhang, J.

2006-01-01T23:59:59.000Z

444

Conjugate heat transfer in channels with internal longitudinal corrugated fins  

E-Print Network [OSTI]

@~ and @?, i' or Various K; F = 0. 020 and L = 0. 215 . 3. 10 Local Surface Temperature versus B, ~ and Q? for ql and q2 Boundary Conditions; F = 0. 020 and L = 0. 215 3. 11 Local Surface Heat Flux versus +~ and Rq~ for Various 6; F = 0. 02 3. 12 Local... axis length of the channel. Ar ? Flow cross-sectional area in the calculation domain. Ay~ ? Flow cross-sectional area in the calculation domain when there is no fin. c ? Specific heat of the flowing fluid, D ? Height of the flow cross section. Ds...

Ackermann, J. Albert

2012-06-07T23:59:59.000Z

445

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

E-Print Network [OSTI]

Measurements and Predictions of the Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Transfer at the Tube-Fin Junction for Louvered Fin Heat Exchangers Abstract The dominant thermal resistance used to increase heat transfer by initiating new boundary layer growth and increasing surface area

Thole, Karen A.

446

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 the formation of streamwise vortices and increase heat transfer between a working fluid and the surface on which the winglets are placed. This study investigates the use of delta winglets to augment heat transfer on the tube

Thole, Karen A.

447

Steam-Methane Reformer Kinetic Computer Model with Heat Transfer and Geometry Options  

SciTech Connect (OSTI)

A kinetic computer model of a steam/methane reformer has been developed as a design and analytical tool for a fuel cell system's fuel conditioner. This model has reaction, geometry, flow arrangement, and heat transfer options. Model predictions have been compared to previous experimental data, and close agreement was obtained. Initially, the Leva-type, packed-bed, heat transfer correlations were used. However, calculations based upon the reacting, reformer gases indicate a considerably higher heat transfer coefficient for this reforme design. Data analysis from similar designs in the literature also shows this phenomenon. This is thought to be reaction-induced effect, brought about by the changing of gas composition, the increased gas velocity, the lower catalyst temperature during reaction, and the higher thermal and reaction gradients involved in compact fuel cell reformer designs. Future experimental work is planned to verify the model's predictions further.

Murray, A.P.; Snyder, T.S.

1985-04-01T23:59:59.000Z

448

Small distance expansion for radiative heat transfer between curved objects  

E-Print Network [OSTI]

We develop a small distance expansion for the radiative heat transfer between gently curved objects, in terms of the ratio of distance to radius of curvature. A gradient expansion allows us to go beyond the lowest order proximity transfer approximation. The range of validity of such expansion depends on temperature as well as material properties. Generally, the expansion converges faster for the derivative of the transfer than for the transfer itself, which we use by introducing a near-field adjusted plot. For the case of a sphere and a plate, the logarithmic correction to the leading term has a very small prefactor for all materials investigated.

Vladyslav A. Golyk; Matthias Krüger; Alexander P. McCauley; Mehran Kardar

2012-10-12T23:59:59.000Z

449

An analog analysis of transient heat flow in solids with temperature-dependent thermal properties  

E-Print Network [OSTI]

) used a nonlinear material known as Metrosil to simulate the nonlinear variations of thermal properties for combined conductive and radiant heat transfer. Since that time, Friedmann (8) has used nonlinear resistances in conjunction with an electronic... at end of this thesis. K = thermal conductivity of heat conducting media, and K and S are functions of the temperature t. Since the formation of these equations, solutions of transient heat flow problems involving materials in which the thermal...

Lee, Dwain Edward

2012-06-07T23:59:59.000Z

450

Experimental and numerical heat transfer analysis of a V-cavity absorber for linear parabolic trough solar collector  

Science Journals Connector (OSTI)

Abstract In the present study, a V-cavity absorber with rectangular fins that can be used in the linear parabolic trough collector (PTC) system was proposed and investigated both theoretically and experimentally. The optical performance of the absorber was studied by means of Monte-Carlo ray-tracing (MCRT) method. An energy balance model and a more detailed three-dimensional numerical model were developed to analyze the flow and heat transfer characteristics. Moreover, an experimental setup was built to validate the theoretical analysis. A reasonable agreement between the theoretical and experimental results was achieved, which proves the feasibility and reliability of the models. The results show that the sunlight could be reflected repeatedly by the triangle shape and nearly no sunlight escapes. The absorber with rectangular fins has a better heat transfer performance with higher outlet temperature of heat transfer fluid (HTF), lower temperature of heating surface and lower heat loss than those of absorber without fins. The effects of heat flux distribution, mass flow rate and direct normal irradiance on the heat transfer performance were further discussed. In addition, the variations of the heat transfer coefficient along z axial direction with different mass flow rates were also calculated based on the numerical results.

X. Xiao; P. Zhang; D.D. Shao; M. Li

2014-01-01T23:59:59.000Z

451

Method of measuring heat influx of a cryogenic transfer system. [Patent application  

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, R.C.; Zelipsky, S.A.; Rezmer, R.R.; Smelser, P.

1980-10-29T23:59:59.000Z

452

Turbulent heat transfer and friction in a segmental channel that simulates leading-edge cooling channels of modern turbine blades  

E-Print Network [OSTI]

. Steady state heat transfer experiments for three channel cross sections, ribbed curved wall-to-smooth flat wall heat flux ratio of 0.0, 1.0, 2.0, 4.0, 6.0, and infinity, and mass flow rates corresponding to Reynolds numbers between 10 000 and 70 000...

Spence, Rodney Brian

2012-06-07T23:59:59.000Z

453

A Similarity Analysis for Heat Transfer in Newtonian and Power Law Fluids Using the Instantaneous Wall Shear Stress  

E-Print Network [OSTI]

This paper presents a technique that collapses existing experimental data of heat transfer in pipe flow of Newtonian and power law fluids into a single master curve. It also discusses the theoretical basis of heat, mass and momentum analogies and the implications of the present analysis to visualisations of turbulence.

Trinh, K T; Kiaka, N K

2010-01-01T23:59:59.000Z

454

"Developing novel heat transfer diagnostics for nanosystems."  

E-Print Network [OSTI]

and development of electronic devices, power generation modules, and waste energy harvesting techniques alloys. Thermal conductivity of bismuth-doped III-V alloys Thermoelectric power generation (TPG) has become an increasingly popular technology for waste heat recovery in the last few years. The efficiency

Acton, Scott

455

Heat transfer and hydraulic resistance in a short plane-parallel duct with artificially roughened walls  

Science Journals Connector (OSTI)

Experimental heat transfer and hydraulic resistance data are correlated by means of dimensionless relationships.

V. G. Pavlovskii; Yu. M. Dedusenko

1969-12-01T23:59:59.000Z

456

Exergy analysis of second-generation micro heat sinks under single-phase and flow boiling conditions  

Science Journals Connector (OSTI)

A parametric study of exergy efficiency was conducted for five micro pin fin heat sinks of different spacing and shapes. Of the four micro pin fin heat sinks tested under single-phase flow conditions, those with better heat transfer performance yielded superior exergy efficiencies. The use of R-123 in place of water as working fluid was found to enhance exergetic performance at the expense of reduced heat transfer performance. The exergy analysis was also extended to the flow boiling of R-123 in an additional hydrofoil-based micro pin fin heat sink. It was found that exergy efficiencies decreased with mass velocity.

Ali Kosar

2010-01-01T23:59:59.000Z

457

Effect of electric field on heat transfer performance of automobile radiator at low frontal air velocity  

Science Journals Connector (OSTI)

The effect of electric field on the performance of automobile radiator is investigated in this work. In this experiment, a louvered fin and flat tube automobile radiator was mounted in a wind tunnel and there was heat exchange between a hot water stream circulating inside the tube and a cold air stream flowing through the external surface. The electric field was supplied on the airside of the heat exchanger and its supply voltage was adjusted from 0 kV to 12 kV. From the experiment, it was found that the unit with electric field pronounced better heat transfer rate, especially at low frontal velocity of air. The correlations for predicting the air-side heat transfer coefficient of the automobile radiator, with and without electric field, at low frontal air velocity were also developed and the predicted results agreed very well with the experimental data.

S. Vithayasai; T. Kiatsiriroat; A. Nuntaphan

2006-01-01T23:59:59.000Z

458

Group solution for unsteady free-convection flow from a vertical moving plate subjected to constant heat flux  

Science Journals Connector (OSTI)

The problem of heat and mass transfer in an unsteady free-convection flow over a continuous moving vertical sheet in an ambient fluid is investigated for constant heat flux using the group theoretical method. The nonlinear coupled partial differential ... Keywords: 22E05, 35Q53, 54H15, Free convective flow, Group theoretic method, Prandtl number, Thermal boundary layer

M. Kassem

2006-03-01T23:59:59.000Z

459

Volume Averaging Theory (VAT) based modeling and closure evaluation for fin-and-tube heat exchangers  

E-Print Network [OSTI]

made to simulate the heat transfer and fluid flow across theanalysis of heat transfer and fluid flow in a three-lent flow and heat transfer in a porous layer. J Fluids Eng

Zhou, Feng; Catton, Ivan

2012-01-01T23:59:59.000Z

460

Micro-Columnated Loop Heat Pipe: The Future of Electronic Substrates  

E-Print Network [OSTI]

4.5.1 Fluid Flow and Heat Transfer Characteristics . . 4.5.2v ? T i = 5 K. Fluid Flow and Heat Transfer Characteristicsmodeling of heat transfer and fluid flow phenomena at the

Dhillon, Navdeep Singh

2012-01-01T23:59:59.000Z

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


461

Development of Closure for Heat Exchangers Based on Volume Averaging Theory  

E-Print Network [OSTI]

Analysis of Fluid Flow and Heat Transfer Characteristics inFigure 4.16: Fluid flow and heat transfer over a backwardof modeling the fluid flow and heat transfer within such

Zhou, Feng

2014-01-01T23:59:59.000Z

462

MODELING OF HEAT TRANSFER IN ROOMS IN THE MODELICA  

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

463

THERM: Two-Dimensional Building Heat-Transfer Modeling  

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

464

Heat Transfer in Projecting and Sloped Fenestration Products  

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

465

Thaw flow control for liquid heat transport systems  

DOE Patents [OSTI]

In a liquid metal heat transport system including a source of thaw heat for use in a space reactor power system, the thaw flow throttle or control comprises a fluid passage having forward and reverse flow sections and a partition having a plurality of bleed holes therein to enable fluid flow between the forward and reverse sections. The flow throttle is positioned in the system relatively far from the source of thaw heat.

Kirpich, Aaron S. (Broomall, PA)

1989-01-01T23:59:59.000Z

466

Convective heat transfer in a locally heated plane incompressible fluid layer  

Science Journals Connector (OSTI)

The problem of convection in a plane horizontal layer of incompressible fluid with rigid boundaries when the temperature is ... . Together with the wellknown solutions which describe heat transfer for the linear ...

S. N. Aristov; K. G. Shvarts

2013-05-01T23:59:59.000Z

467

A numerical investigation of natural convection heat transfer within horizontal spent-fuel assemblies  

SciTech Connect (OSTI)

A numerical investigation of natural convection heat transfer is carried out for a single, horizontal, spent-fuel assembly in an environment typical of spent-fuel transportation systems as well as some dry storage/disposal scenarios. The objective is to predict computationally the convective heat transfer trends for horizontal spent fuel and to compare the results to data taken in a supporting experimental effort. The predicted data consist of thermal and flow fields throughout the assembly for a wide range of Rayleigh number, as well as numerically obtained Nusselt-number data that are correlated as a function of Rayleigh number. Both laminar and turbulent approaches are examined for a Boussinesq fluid with Pr = 0.7. The data predict the existence of a conduction-dominated regime, a transition regime, and a convection regime. Compared with the laminar approach, a significant improvement in the predicted Nusselt number is obtained for large Rayleigh numbers when a turbulence model is employed. This lends additional support to the experimental evidence that a transition to turbulent flow occurs for Rayleigh numbers greater than 10{sup 7}. Overall, the numerically predicted heat transfer trends compare well with previously obtained experimental data, and the computed assembly Nusselt numbers generally reside within the range of experimental uncertainty. The predicted thermal and flow fields further provide a numerical flow visualization capability that enhances the understanding of natural convection in horizontal spent fuel and allows improved physical interpretation of the experimental data.

Canaan, R.E. [Lawrence Livermore National Lab., CA (United States); Klein, D.E. [Univ. of Texas System, Austin, TX (United States)

1998-08-01T23:59:59.000Z

468

Thermal Hydraulic Optimization of Nuclear Systems [Heat Transfer and Fluid  

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

469

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

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

470

Advanced Model and Methodology Development [Heat Transfer and Fluid  

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

471

Radiative heat transfer in 2D Dirac materials  

E-Print Network [OSTI]

We compute the radiative heat transfer between two sheets of 2D Dirac materials, including topological Chern insulators and graphene, within the framework of the local approximation for the optical response of these materials. In this approximation, which neglects spatial dispersion, we derive both numerically and analytically the short-distance asymptotic of the near-field heat transfer in these systems, and show that it scales as the inverse of the distance between the two sheets. Finally, we discuss the limitations to the validity of this scaling law imposed by spatial dispersion in 2D Dirac materials.

Pablo Rodriguez-Lopez; Wang-Kong Tse; Diego A. R. Dalvit

2015-02-02T23:59:59.000Z

472

Quantum heat transfer: A Born-Oppenheimer method  

Science Journals Connector (OSTI)

We develop a Born-Oppenheimer-type formalism for the description of quantum thermal transport across hybrid nanoscale objects. Our formalism is suitable for treating heat transfer in the off-resonant regime, where, e.g., the relevant vibrational modes of the interlocated molecule are high relative to typical bath frequencies, and at low temperatures when tunneling effects dominate. A general expression for the thermal energy current is accomplished in the form of a generalized Landauer formula. In the harmonic limit this expression reduces to the standard Landauer result for heat transfer. In the presence of nonlinearities, multiphonon effects are realized.

Lian-Ao Wu and Dvira Segal

2011-05-12T23:59:59.000Z

473

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

474

Enhanced heat transfer using wire-coil inserts for high-heat-load applications.  

SciTech Connect (OSTI)

Enhanced heat-transfer techniques, used to significantly reduce temperatures and thermally induced stresses on beam-strike surfaces, are routinely used at the APS in all critical high-heat-load components. A new heat-transfer enhancement technique being evaluated at the APS involving the use of wire-coil inserts proves to be superior to previously employed techniques. Wire coils, similar in appearance to a common spring, are fabricated from solid wire to precise tolerances to mechanically fit inside standard 0.375-in-diameter cooling channels. In this study, a matrix of wire coils, fabricated with a series of different pitches from several different wire diameters, has been tested for heat-transfer performance and resulting pressure loss. This paper reviews the experimental data and the analytical calculations, compares the data with existing correlations, and interprets the results for APS front-end high-heat-load components.

Collins, J. T.; Conley, C. M.; Attig, J. N.; Baehl, M. M.

2002-09-20T23:59:59.000Z

475

On the correlation of buoyancy-influenced turbulent convective heat transfer to fluids at supercritical pressure  

SciTech Connect (OSTI)

This paper is concerned with buoyancy-influenced turbulent convective heat transfer in vertical tubes for conditions where the physical properties vary strongly with temperature as in fluids at supercritical pressure in the pseudocritical temperature region. An extended physically-based, semi-empirical model is described which has been developed to account for the extreme non-uniformity of properties which can be present in such fluids and lead to strong influences of buoyancy which cause the mean flow and turbulence fields to be modified in such a manner that has a very profound effect on heat transfer. Data for both upward and downward flow from experiments using carbon dioxide at supercritical pressure (8.80, MPa, p/pc=1.19) in a uniformly heated tube of internal diameter 2 mm and length 290 mm, obtained under conditions of strong non-uniformity of fluid properties, are being correlated and fitted using an approach based on the model. It provides a framework for describing the complex heat transfer behaviour which can be encountered in such experiments by means of an equation of simple form. Buoyancy-induced impairment and enhancement of heat transfer is successfully reproduced by the model. Similar studies are in progress using experimental data for both carbon dioxide and water from other sources. The aim is to obtain an in-depth understanding of the mechanisms by which deterioration of heat transfer might arise in sensitive applications involving supercritical pressure fluids, such as high pressure, water-cooled reactors operating above the critical pressure. (authors)

Jackson, J. D. [Univ. of Manchester, Manchester (United Kingdom); Jiang, P. X.; Liu, B. [Tsinghua Univ., Thermal Engineering Dept., Beijing (China)

2012-07-01T23:59:59.000Z

476

Heat transfer and film cooling with steam injection  

E-Print Network [OSTI]

for both coolants was determined for similar blowing rates and was used as a basis for comparisons. Heat transfer coefficients were calcula- ted from the experimental data using a transient analysis. DEDICATION To my wife and family. ACKNOWLEDGEMENTS... LIST OF TABLES PAGE TABLE 1 Variation in the Blowing Rate ------------ 55 TABLE 2 TABLE 3 Typical Air Film Cooling Effectiveness Data Typical Steam Film Cooling Effectiveness Data 62 62 1X LIST OF FIGURES PAGE Figure 1 Comparison of Heat...

Conklin, Gary Eugene

1982-01-01T23:59:59.000Z

477

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

478

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

479

Integration of Heat Transfer, Stress, and Particle Trajectory Simulation  

SciTech Connect (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

480

Retrofit of a Heat-Exchanger Network by Considering Heat-Transfer Enhancement and Fouling  

Science Journals Connector (OSTI)

Besides, for network-topology modifications the capital cost associated with the related pipe and civil work is high, and the negative financial impact of production losses resulting from plant shut down during the lengthy periods of a retrofit is also a concern. ... One way is to add heat-transfer enhancement to the cold side in a heat exchanger to increase the cold-side heat-transfer coefficients, and the other is to change the network structure to reassign the temperature distribution in the network. ... An existing industrial PHT network is simulated using a dynamic, distributed math. ...

Yufei Wang; Robin Smith

2013-06-07T23:59:59.000Z

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481

Enhancement of Heat Transfer in an Artificially Roughened Solar Air Heater  

E-Print Network [OSTI]

Abstract: solar air heater is one of the basic equipment through which solar energy is converted into thermal energy. Solar air heaters, because of their simple in design, are cheap and most widely used collection devices of solar energy. The thermal efficiency of a solar air heater is significantly low because of the low value of the convective heat transfer coefficient between the absorber plate and the air, leading to high absorber plate temperature and high heat losses to the surroundings. This paper presents the study of heat transfer in a solar air heater by using Computational Fluid Dynamics (CFD). The effect of Reynolds number on Nusselt number is investigated. A commercial finite volume package ANSYS FLUENT 12.1 is used to analyze and visualize the nature of the flow across the duct of a solar air heater.

unknown authors

482

Combined heat and mass transfer device for improving separation process  

SciTech Connect (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

483

~) Pergamon Int. J. Heat Mass Transfer. Vol. 39, No. 13, pp. 2653-2662, 1996  

E-Print Network [OSTI]

in the grinding process is presented in this paper. Heat transfer models for the abrasive grain, fluid. Lavine and Jen [4, 5] presented a model to simulate the heat transfer to the workpiece, wheel, and fluid or the convection heat transfer coefficient of the grinding fluid. They assumed that the heat flux into the work

Zhang, Yuwen

484

Condensation heat transfer in square, triangular, and semi-circular mini-channels Melanie Derby a  

E-Print Network [OSTI]

Condensation heat transfer in square, triangular, and semi-circular mini-channels Melanie Derby: Condensation Heat transfer Minichannel Channel shape Correlation a b s t r a c t Condensation heat transfer significant effects on the condensation process, even at lower mass fluxes, while saturation pressure, heat

Peles, Yoav

485

Near-field heat transfer between gold nanoparticle arrays  

SciTech Connect (OSTI)

The radiative heat transfer between gold nanoparticle layers is presented using the coupled dipole method. Gold nanoparticles are modelled as effective electric and magnetic dipoles interacting via electromagnetic fluctuations. The effect of higher-order multipoles is implemented in the expression of electric polarizability to calculate the interactions at short distances. Our findings show that the near-field radiation reduces as the radius of the nanoparticles is increased. Also, the magnetic dipole contribution to the heat exchange becomes more important for larger particles. When one layer is displayed in parallel with respect to the other layer, the near-field heat transfer exhibits oscillatory-like features due to the influence of the individual nanostructures. Further details about the effect of the nanoparticles size are also discussed.

Phan, Anh D., E-mail: anhphan@mail.usf.edu [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States); Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Ba Dinh, Hanoi 10000 (Viet Nam); Phan, The-Long, E-mail: ptlong2512@yahoo.com [Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of); Woods, Lilia M. [Department of Physics, University of South Florida, Tampa, Florida 33620 (United States)

2013-12-07T23:59:59.000Z

486

Castor-1C spent fuel storage cask decay heat, heat transfer, and shielding analyses  

SciTech Connect (OSTI)

This report documents the decay heat, heat transfer, and shielding analyses of the Gesellschaft fuer Nuklear Services (GNS) CASTOR-1C cask used in a spent fuel storage demonstration performed at Preussen Elektra's Wurgassen nuclear power plant. The demonstration was performed between March 1982 and January 1984, and resulted in cask and fuel temperature data and cask exterior surface gamma-ray and neutron radiation dose rate measurements. The purpose of the analyses reported here was to evaluate decay heat, heat transfer, and shielding computer codes. The analyses consisted of (1) performing pre-look predictions (predictions performed before the analysts were provided the test data), (2) comparing ORIGEN2 (decay heat), COBRA-SFS and HYDRA (heat transfer), and QAD and DOT (shielding) results to data, and (3) performing post-test analyses if appropriate. Even though two heat transfer codes were used to predict CASTOR-1C cask test data, no attempt was made to compare the two codes. The codes are being evaluated with other test data (single-assembly data and other cask data), and to compare the codes based on one set of data may be premature and lead to erroneous conclusions.

Rector, D.R.; McCann, R.A.; Jenquin, U.P.; Heeb, C.M.; Creer, J.M.; Wheeler, C.L.

1986-12-01T23:59:59.000Z

487

Generalized constructal optimization for solidification heat transfer process of slab continuous casting based on heat loss rate  

Science Journals Connector (OSTI)

Abstract Based on constructal theory, generalized constructal optimization of a solidification heat transfer process of slab continuous casting is carried out by taking a complex function as optimization objective. The complex function is composed of the functions of the heat loss rate and surface temperature gradient of the slab subjected to the constraints of shell thickness, surface temperature and liquid core length of the slab. For the specified total water flow rate, the “optimal construct” of the water distribution in the secondary cooling zone is obtained. Comparing the optimal results with the initial ones, it is shown that the complex function, the functions of the heat loss rate and the surface temperature gradient after optimization are decreased by 35.04%, 2.14% and 59.48%, respectively. Therefore, the scheme of the “optimal construct” of the water distribution reduces the heat loss rate and surface temperature gradient of the slab simultaneously, that is, improves its energy retention and quality simultaneously. The optimization results obtained in this paper can provide some guidelines for parameter designs and dynamic operations of the solidification heat transfer process of slab continuous casting.

Huijun Feng; Lingen Chen; Zhihui Xie; Zemin Ding; Fengrui Sun

2014-01-01T23:59:59.000Z

488

Deep Eutectic Salt Formulations Suitable as Advanced Heat Transfer Fluids  

SciTech Connect (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

489

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

Open Energy Info (EERE)

of geothermal energy. As a consequence of anomalously high temperature, the mechanical lithosphere is thin and its total strength can be reduced by almost one order of...

490

Heat flow in the postquasistatic approximation  

SciTech Connect (OSTI)

We apply the postquasistatic approximation to study the evolution of spherically symmetric fluid distributions undergoing dissipation in the form of radial heat flow. For a model that corresponds to an incompressible fluid departing from the static equilibrium, it is not possible to go far from the initial state after the emission of a small amount of energy. Initially collapsing distributions of matter are not permitted. Emission of energy can be considered as a mechanism to avoid the collapse. If the distribution collapses initially and emits one hundredth of the initial mass only the outermost layers evolve. For a model that corresponds to a highly compressed Fermi gas, only the outermost shell can evolve with a shorter hydrodynamic time scale.

Rodriguez-Mueller, B. [Computational Science Research Center, College of Sciences, San Diego State University, San Diego, California (United States); Peralta, C. [Deutscher Wetterdienst, Frankfurter Strasse 135, 63067 Offenbach (Germany); School of Physics, University of Melbourne, Parkville, VIC 3010 (Australia); Barreto, W. [Centro de Fisica Fundamental, Facultad de Ciencias, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of); Rosales, L. [Laboratorio de Fisica Computacional, Universidad Experimental Politecnica, 'Antonio Jose de Sucre', Puerto Ordaz (Venezuela, Bolivarian Republic of)

2010-08-15T23:59:59.000Z

491

Heat flow in the postquasistatic approximation  

E-Print Network [OSTI]

We apply the postquasistatic approximation to study the evolution of spherically symmetric fluid distributions undergoing dissipation in the form of radial heat flow. For a model which corresponds to an incompressible fluid departing from the static equilibrium, it is not possible to go far from the initial state after the emission of a small amount of energy. Initially collapsing distributions of matter are not permitted. Emission of energy can be considered as a mechanism to avoid the collapse. If the distribution collapses initially and emits one hundredth of the initial mass only the outermost layers evolve. For a model which corresponds to a highly compressed Fermi gas, only the outermost shell can evolve with a shorter hydrodynamic time scale.

B. Rodríguez-Mueller; C. Peralta; W. Barreto; L. Rosales

2010-05-10T23:59:59.000Z

492

The International Heat Flow Commission | Open Energy Information  

Open Energy Info (EERE)

The International Heat Flow Commission The International Heat Flow Commission Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: The International Heat Flow Commission Details Activities (1) Areas (1) Regions (0) Abstract: Unavailable Author(s): A. E. Beck, V. Cermak Published: Geothermics, 1989 Document Number: Unavailable DOI: Unavailable Source: View Original Journal Article Data Acquisition-Manipulation (Beck & Cermak, 1989) Unspecified Retrieved from "http://en.openei.org/w/index.php?title=The_International_Heat_Flow_Commission&oldid=387748" Category: Reference Materials What links here Related changes Special pages Printable version Permanent link Browse properties 429 Throttled (bot load) Error 429 Throttled (bot load) Throttled (bot load) Guru Meditation: XID: 1863774514

493

Temperature, heat flow maps and temperature gradient holes |...  

Open Energy Info (EERE)

Temperature, heat flow maps and temperature gradient holes Author T. G. Zacharakis Organization Colorado Geological Survey in Cooperation with the U.S. Department of Energy...

494

Ch. VII, Temperature, heat flow maps and temperature gradient...  

Open Energy Info (EERE)

Ch. VII, Temperature, heat flow maps and temperature gradient holes Author T. G. Zacharakis Editor T. G. Zacharakis Published Colorado Geological Survey in Cooperation with the...

495

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

Open Energy Info (EERE)

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

496

Convective heat transfer in an annular porous layer with centrifugal force field  

SciTech Connect (OSTI)

The present study deals with natural convection in an annular porous layer under the influence of a centrifugal force field. It is assumed that the outer boundary is heated by a constant heat flux, while the inner boundary is perfectly insulated. The problem is formulated in terms of Darcy-Boussinesq equations and solved using analytical and numerical techniques. An analytical solution for the flow and heat transfer variables, based on a concentric flow assumption, is obtained in terms of the Rayleigh number and the radius ratio. Finite amplitude results are verified by a numerical approach. Predicted thresholds in terms of critical Rayleigh numbers are verified by a linear stability analysis. Results obtained from the numerical approach indicate the existence of multiple solutions differing by the number of cells involved.

Aboubi, K.; Robillard, L.; Bilgen, E. [Univ. of Montreal, Quebec (Canada). Dept. of Mechanical Engineering

1995-09-01T23:59:59.000Z

497

Residence time distribution and heat transfer in circular pipe fitted with longitudinal rectangular wings  

Science Journals Connector (OSTI)

Abstract Numerical simulations are used to analyze the heat and mass transfer in a circular pipe fitted with longitudinal rectangular vortex generators for Reynolds number between 7500 and 15,000 based on the pipe diameter. The aim of the present study is to test and quantify the mixing efficiency of a new solution able to avoid the bypass region that exists in the center of the high efficiency vortex static mixer (HEV), and also to enhance the heat transfer without increasing the pressure losses. The rectangular wings used here generate each a streamwise counter-rotating vortex pair sweeping the volume of the mixer and act as internal agitator on the flow. The particle dispersion is investigated by analyzing Poincaré sections and by studying the residence time distribution (RTD). The two approaches show much better mass transfer performance and better mixing homogeneity for the new wings arrangement. The heat transfer is also investigated and it is shown that the thermal enhancement factor in the new arrangement is much greater than that of the conventional systems used in the industry. When compared to the HEV heat exchangers it is shown that the thermal enhancement in the present configuration reaches about 40% relative to the classic HEV and 15% relative to the reversed HEV.

Charbel Habchi; Jean-Luc Harion

2014-01-01T23:59:59.000Z

498

THERMOSIPHON WATER HEATERS WITH HEAT EXCHANGERS  

E-Print Network [OSTI]

communications). Heat transfer fluid is 60% o-o1vco1 bycharacteristics, heat transfer fluids, flow resistances,of a non- freezing heat transfer fluid circulating in a loop

Mertol, Atila

2012-01-01T23:59:59.000Z

499

Simultaneous heat and mass transfer in absorption of gases in laminar liquid films  

SciTech Connect (OSTI)

A theoretical analysis of the combined heat and mass transfer process taking place in the absorption of a gas or vapor into a laminar liquid film is described. This type of process, which occurs in many gas-liquid systems, often releases only a small amount of heat, making the process almost isothermal. In some cases, however, the heat of absorption is significant and temperature variations cannot be ignored. One example, from which the present study originated, is in absorption heat pumps where mass transfer is produced specifically to generate a temperature change. The model analyzed describes a liquid film that flows over an inclined plane and has its free surface in contact with stagnant vapor. The absorption process at the surface creates nonuniform temperature and concentration profiles in the film, which develop until equilibrium between the liquid and vapor is achieved. The energy and diffusion equations are solved simultaneously to give the temperature and concentration variations at the interface and the wall. Two cases of interest are considered: constant-temperature and adiabatic walls. The Nusselt and Sherwood numbers are expressed in terms of the operating parameters, from which heat and mass transfer coefficients can be determined. The Nusselt and Sherwood numbers are found to depend on the Peclet and Lewis numbers as well as on the equilibrium characteristics of the working materials.

Grossman, G

1982-09-01T23:59:59.000Z

500

Local heat transfer distribution in a two-pass trapezoidal channel with a 180 [degree] turn via transient liquid crystal technique  

E-Print Network [OSTI]

This experimental research investigates the heat transfer characteristics of air flows in serpentine cooling channels in stationary stator blades of gas turbines. The internal cooling channels are modeled as a smooth two-pass channel of trapezoidal...

Endley, Saurabh

2012-06-07T23:59:59.000Z