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Handbook of heat transfer

TL;DR: In this article, the analogy between heat and mass transfer is covered and applied in the analysis of heat transfer by conduction, convection and radiation, and the analysis is performed by using the handbook of numerical heat transfer.
Abstract: Handbook of Numerical Heat Transfer Free Full Download Links from Multiple Mirrors added by DL4W on 2015-04-10 02:13:35. Handbook of heat transfer / editors, W.M. Rohsenow, J.P. Hartnett. Y.I. Cho. m 3rd ed. p. cm. Includes bibliographical references and index. ISBN 0-07053555-8. Students investigate heat transfer by conduction, convection and radiation. The analogy between heat and mass transfer is covered and applied in the analysis.
Citations
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Journal ArticleDOI
TL;DR: In this article, the authors considered seven slip mechanisms that can produce a relative velocity between the nanoparticles and the base fluid and concluded that only Brownian diffusion and thermophoresis are important slip mechanisms in nanofluids.
Abstract: Nanofluids are engineered colloids made of a base fluid and nanoparticles (1-100 nm) Nanofluids have higher thermal conductivity' and single-phase heat transfer coefficients than their base fluids In particular the heat transfer coefficient increases appear to go beyond the mere thermal-conductivity effect, and cannot be predicted by traditional pure-fluid correlations such as Dittus-Boelter's In the nanofluid literature this behavior is generally attributed to thermal dispersion and intensified turbulence, brought about by nanoparticle motion To test the validity of this assumption, we have considered seven slip mechanisms that can produce a relative velocity between the nanoparticles and the base fluid These are inertia, Brownian diffusion, thermophoresis, diffusioplwresis, Magnus effect, fluid drainage, and gravity We concluded that, of these seven, only Brownian diffusion and thermophoresis are important slip mechanisms in nanofluids Based on this finding, we developed a two-component four-equation nonhomogeneous equilibrium model for mass, momentum, and heat transport in nanofluids A nondimensional analysis of the equations suggests that energy transfer by nanoparticle dispersion is negligible, and thus cannot explain the abnormal heat transfer coefficient increases Furthermore, a comparison of the nanoparticle and turbulent eddy time and length scales clearly indicates that the nanoparticles move homogeneously with the fluid in the presence of turbulent eddies so an effect on turbulence intensity is also doubtful Thus, we propose an alternative explanation for the abnormal heat transfer coefficient increases: the nanofluid properties may vary significantly within the boundary layer because of the effect of the temperature gradient and thermophoresis For a heated fluid, these effects can result in a significant decrease of viscosity within the boundary layer, thus leading to heat transfer enhancement A correlation structure that captures these effects is proposed

5,329 citations

Journal ArticleDOI
TL;DR: In this article, the status of worldwide research in the thermal conductivity of carbon nanotubes and their polymer nanocomposites is reviewed, as well as the relationship between thermal conductivities and the micro- and nano-structure of the composites.

2,102 citations

01 Jan 2011
TL;DR: In this paper, the non-similar solutions are presented which depend on the Magnetic parameter M respectively, the obtained equations have been solved by explicit finite difference method and temperature and concentration profiles are discussed for the different values of the above parameters with different time steps.
Abstract: Unsteady heat and mass flow of a nanofluid past a stretching sheet with thermal radiation in the presence of magnetic field is studied. To obtain non-similar equation, continuity, momentum, energy and concentration equations have been non-dimensionalised by usual transformation. The non-similar solutions are presented here which depends on the Magnetic parameter M respectively . The obtained equations have been solved by explicit finite difference method. The temperature and concentration profiles are discussed for the different values of the above parameters with different time steps.

956 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present an overview of various cooling methods that can be employed for photovoltaic cells, including linear concentrators, single-cell arrangements, and densely packed photovolastic cells.

678 citations

Book
01 Jan 2013
TL;DR: In this paper, district heating and cooling systems substitute ordinary primary energy supply for heating, and increase both energy efficiency and decarbonisation in the global energy system, however, they are highly underestimated in contemporary energy policy, both nationally and internationally.
Abstract: District heating and cooling systems move heat in urban areas. Heat and cold are generated in central supply units by heat or cold recycling, renewables, or by direct heat or cold generation. The heat and cold demands should be concentrated in order to keep low distribution costs. District heating and cooling systems substitute ordinary primary energy supply for heating and cooling. Therefore, district heating and cooling increase both energy efficiency and decarbonisation in the global energy system. However, district heating and cooling is a highly underestimated energy efficiency and decarbonisation method in contemporary energy policy, both nationally and internationally.

446 citations

References
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1,799 citations


"Handbook of heat transfer" refers background or methods or result in this paper

  • ...51 Fu l l y deve loped Nusselt numbers for laminar f l ow in a t rapezoida l p ipe [172]....

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  • ...53 Fully Developed Fluid Flow and Heat Transfer Characteristics of Sine Ducts [172]...

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  • ...These results are based on the analysis by Shah [172]....

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  • ...27b, have been investigated by Shah [172]....

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  • ...The fully developed flow and heat transfer characteristics of rhombic ducts obtained by Shah [172] are shown in Table 5....

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Journal ArticleDOI
TL;DR: The discrete dipole approximation (DDA) was extended to incorporate the effects of radiative reaction and to allow for possible anisotropy of the dielectric tensor of the material as mentioned in this paper.
Abstract: The discrete dipole approximation (DDA), a flexible method for computing scattering of radiation by particles of arbitrary shape, is extended to incorporate the effects of radiative reaction and to allow for possible anisotropy of the dielectric tensor of the material. Formulas are given for the evaluation of extinction, absorption, scattering, and polarization cross sections. A simple numerical algorithm based on the method of conjugate gradients is found to provide an efficient and robust method for obtaining accurate solutions to the scattering problem. The method works well for absorptive, as well as dielectric, grain materials. Two validity criteria for the DDA are presented. The DDA is then used to compute extinction cross sections for spherical graphite grains and to calculate extinction cross sections for nonspherical graphite grains with three different geometries. It is concluded that the interstellar 2175 A extinction feature could be produced by small graphite grains which should have aspect ratios not far from unity. 35 references.

1,457 citations


"Handbook of heat transfer" refers background or methods in this paper

  • ...Migay [173] obtained another relation for 2~ = 90 °, as follows:...

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  • ...27c, the velocity distribution and friction factors for fully developed laminar flow are expressed by the following set of equations suggested by Migay [173]:...

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  • ...7, the effect of Pr has been found to be stronger: the effect of low Prandt l n u m b e r on cavities with adiabat ic walls and H/L = 1 was invest igated, using a C F D code, by Lage and Bejan [173]....

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Journal ArticleDOI
TL;DR: The HITRAN molecular absorption database as mentioned in this paper contains line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies, including chlorofluorocarbons and other molecular species that are not amenable to line-by-line representation.
Abstract: We describe in this paper the modifications, improvements, and enhancements to the HITRAN molecular absorption database that have occurred in the two editions of 1991 and 1992 The current database includes line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies This line-by-line portion of HITRAN presently contains about 709,000 transitions between 0 and 23,000/cm and contains three molecules not present in earlier versions: COF2, SF6, and H2S The HITRAN compilation has substantially more information on chlorofluorocarbons and other molecular species that exhibit dense spectra which are not amenable to line-by-line representation The user access of the database has been advanced, and new media forms are now available for use on personal computers

1,442 citations


"Handbook of heat transfer" refers methods or result in this paper

  • ...To avoid computational complexity, the following simple approximations have been suggested [156]: u y " Umax [1 (z)ml 5226, Umaxum (m X)(n l)m n 5227,...

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  • ...147) This relation fits the data of Kaviany and Mittal [156] over the range of their data, 1 < Ra < 102, for polyurethane foams with ¢~ = 0....

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  • ...The above approximations are within +10 percent of the analytical results [156, 157] and the numerical results [158]....

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Book ChapterDOI
TL;DR: In this article, the authors examined the effect of roughness on boundary layer characteristics and showed that the wall is aerodynamically smooth for a turbulent boundary layer if the roughness elements are so small as to be buried in the laminar sublayer.
Abstract: Publisher Summary This chapter discusses the simple case of the turbulent boundary layer in a constant pressure field and considers the complex problem of the effects of pressure gradients, and variable wall roughness The concepts of boundary layer phenomena, in general, and turbulent boundary layers, in particular, have found application in a wide range of fields including aeronautics, guided missiles, marine engineering, hydraulics, meteorology, oceanography, chemical engineering, atomic reactors, and the flow of liquids and gases in the human body Many ideas for turbulent boundary layers involve assumptions other than those for turbulent shear stresses and in these cases, the validity of the results is examined first for laminar layers and then interpreted in the light of the possible shear stress patterns of turbulent layers The effect of roughness on boundary layer characteristics is examined in the chapter The wall is aerodynamically smooth for a turbulent boundary layer if the roughness elements are so small as to be buried in the laminar sublayer Pressure gradients, Reynolds number, or roughness does not affect the constants of proportionality The assumption of a constant outer viscosity has been investigated only for the case of equilibrium layers

1,367 citations


"Handbook of heat transfer" refers background in this paper

  • ...Analyses and measurements related to transient heat transfer on vertical surfaces have been reviewed by Ede [79]....

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  • ...31 Universal velocity profile for an incompressible turbulent boundary layer near the surface ("law of the wall") [79]....

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  • ...Clauser [79] made two observations regarding turbulent boundary layer velocity profiles that have direct influence on convective heating analyses....

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  • ...149 applies to equilibrium boundary layers, as defined by Clauser [79], where (6*/%) dP/dx is constant along the surface....

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Book ChapterDOI
TL;DR: In this paper, the authors discuss the heat transfer and the hydraulic resistance of single tubes, and the banks of tubes of various arrangements in flows of gases and viscous liquids, and highlight the influence of the physical properties of fluids on heat transfer.
Abstract: Publisher Summary This chapter discusses the heat transfer and the hydraulic resistance of single tubes, and the banks of tubes of various arrangements in flows of gases and viscous liquids. The focus is on the important problems of the heat transfer and the hydraulic resistance of tubes, in particular with the heat transfer of single tubes, banks of tubes, and systems of tubes in crossflow. The chapter also highlights the influence of the physical properties of fluids on heat transfer. Extensive experimental data will be analyzed and will include investigations of banks of tubes of various arrangements, and a single tube in crossflow in the range of Prandtl number from 0.7 to 500 and that of Reynolds number from 1 to 2xl0 6 .

1,181 citations


"Handbook of heat transfer" refers background or methods in this paper

  • ...Average and local heat transfer data for tube banks have been summarized by Zukauskas [67]....

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  • ...Investigators Correlations Remarks 1 6,6 ,0] Haaland [67] - ~ = 3....

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  • ...4; Zukauskas [67] recommends a value of 0....

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  • ...These metric coefficients can also be generated by means of the following formula [67]:...

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  • ...The metric coefficients are defined by the general line element ds expressed in terms of the differentials of arc lengths on the coordinate lines [67]...

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