Academic literature on the topic 'Radiative Heat Transfer Rate'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Radiative Heat Transfer Rate.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Radiative Heat Transfer Rate"

1

Liu, L. H., and S. X. Chu. "On the Entropy Generation Formula of Radiation Heat Transfer Processes." Journal of Heat Transfer 128, no. 5 (October 21, 2005): 504–6. http://dx.doi.org/10.1115/1.2190695.

Full text
Abstract:
Because thermal radiation is a long-range phenomenon, the local radiative heat flux is dependent on the temperature distribution of the entire enclosure under consideration and is not determined by the local temperature gradient. In the community of heat transfer, traditionally, the conduction-type formula of entropy generation rate is used to calculate the entropy generation rate of radiation heat transfer. In the present study, three counterexamples are considered. The discrete ordinates method is employed to solve the radiative transfer equation and then solve the radiative entropy generation rate. The results show that the traditional formulas of entropy generation rate for heat transfer generally cannot be used to calculate the local entropy generation rate of radiation heat transfer. Only in optically extremely thick situations, the traditional formula of entropy generation rate for heat transfer can be approximately used to calculate the local entropy generation rate of radiation heat transfer.
APA, Harvard, Vancouver, ISO, and other styles
2

Zhang, Chong, Zhongnong Zhang, and Chun Lou. "Thermodynamic Irreversibility Analysis of Thermal Radiation in Coal-Fired Furnace: Effect of Coal Ash Deposits." Materials 16, no. 2 (January 13, 2023): 799. http://dx.doi.org/10.3390/ma16020799.

Full text
Abstract:
In this paper, a three-dimensional (3-D) high-temperature furnace filled with a gas-solid medium was investigated, and the radiative transfer equation and the radiative entropy transfer equation in the chamber were applied in order to analyze the effect of coal deposits on thermal radiation. The heat flux on the walls of the furnace and the entropy generation rate were determined due to the irreversibility of the radiative heat transfer process in the furnace. Furthermore, the effect of ash deposits on the wall surface on the irreversibility of the radiation heat transfer process was investigated. The numerical results show that when burning bituminous and sub-bituminous coal, ash deposits in the furnace led to a 48.2% and 63.2% decrease in wall radiative heat flux and a 9.1% and 12.4% decrease in the radiative entropy rate, respectively. The ash deposits also led to an increase in the entropy generation number and a decrease in the thermodynamic efficiency of the radiative heat transfer process in the furnace.
APA, Harvard, Vancouver, ISO, and other styles
3

Saleem, M., M. A. Hossain, Suvash C. Saha, and Y. T. Gu. "Heat Transfer Analysis of Viscous Incompressible Fluid by Combined Natural Convection and Radiation in an Open Cavity." Mathematical Problems in Engineering 2014 (2014): 1–14. http://dx.doi.org/10.1155/2014/412480.

Full text
Abstract:
The effect of radiation on natural convection of Newtonian fluid contained in an open cavity is investigated in this study. The governing partial differential equations are solved numerically using the Alternate Direct Implicit method together with the Successive Overrelaxation method. The study is focused on studying the flow pattern and the convective and radiative heat transfer rates are studied for different values of radiation parameters, namely, the optical thickness of the fluid, scattering albedo, and the Planck number. It was found that, in the optically thin limit, an increase in the optical thickness of the fluid raises the temperature and radiation heat transfer of the fluid. However, a further increase in the optical thickness decreases the radiative heat transfer rate due to increase in the energy level of the fluid, which ultimately reduces the total heat transfer rate within the fluid.
APA, Harvard, Vancouver, ISO, and other styles
4

Budaev, Bair V., and David B. Bogy. "The role of EM wave polarization on radiative heat transfer across a nanoscale gap." Journal of Applied Physics 132, no. 5 (August 7, 2022): 054903. http://dx.doi.org/10.1063/5.0094382.

Full text
Abstract:
This work presents a novel study of radiative heat transfer between closely separated plates based on an extension of Planck’s spectrum of thermal radiations to systems with a steady heat flux. This extension together with electromagnetic wave theory is chosen specifically to avoid the commonly used so-called fluctuation dissipation theory, which is also limited to equilibrium systems. The spectrum of thermal radiation with a heat flux is described by the introduction of an analog of a chemical potential, which creates a bias toward the direction of heat transfer. This is the first comprehensive study of radiative heat transfer based on the generalization of Planck’s spectrum for systems with a heat flux, which eliminates contradictions arising when a heat flux is described in terms of the laws limited to equilibrium systems. The total heat flux is split into fluxes carried by waves with different frequencies, directions of propagation, and polarizations. This simplifies the analysis because due to the stochastic independence, the energy fluxes of such waves are additive, and this also reveals that the heat carrying capacity of radiation with the parallel polarization is significantly higher than that of the perpendicularly polarized radiation. This suggests that the rate of radiative heat transfer may be noticeably increased by the control of the polarization of thermal radiation.
APA, Harvard, Vancouver, ISO, and other styles
5

Bayazitoglu, Y., and P. V. R. Suryanarayana. "Transient Radiative Heat Transfer From a Sphere Surrounded by a Participating Medium." Journal of Heat Transfer 111, no. 3 (August 1, 1989): 713–18. http://dx.doi.org/10.1115/1.3250741.

Full text
Abstract:
Transient radiative cooling of a solid or liquid sphere in space, surrounded by a radiatively participating vapor cloud, is considered. A quasi-steady assumption is applied to the radiation transfer in the medium, with the unsteadiness being retained at the inner spherical boundary. The problem is solved by applying the third-order (P3) spherical harmonics approximation to the radiative transfer equation for the participating cloud, and a finite difference scheme for transient conduction in the sphere. In general, the presence of a participating medium decreases the cooling rate of the sphere, and cooling curves are presented to show this effect. Effective emissivity of the surface in the presence of a surrounding medium is evaluated, and an approximate explicit equation is given.
APA, Harvard, Vancouver, ISO, and other styles
6

Nguyen, Phuc-Danh, Huu-Tri Nguyen, Pascale Domingo, Luc Vervisch, Gabriel Mosca, Moncef Gazdallah, Paul Lybaert, and Véronique Feldheim. "Flameless combustion of low calorific value gases, experiments, and simulations with advanced radiative heat transfer modeling." Physics of Fluids 34, no. 4 (April 2022): 045123. http://dx.doi.org/10.1063/5.0087077.

Full text
Abstract:
Thermal radiation is the dominant mode of heat transfer in many combustion systems, and in typical flameless furnaces, it can represent up to 80% of the total heat transfer. Accurate modeling of radiative heat transfer is, thus, crucial in the design of these large-scale combustion systems. Thermal radiation impacts the thermochemistry, thereby the energy efficiency and the temperature sensitive species prediction, such as NOx and soot. The requirement to accurately describe the spectral dependence of gaseous radiative properties of combustion products interacts with the modeling of finite rate chemistry effects and conjugates heat transfer and turbulence. Additionally, because of the multiple injection of fuels and/or oxidizers of various compositions, case-specific radiative properties' expressions are required. Along these lines, a comprehensive modeling to couple radiation and combustion in reacting flows is attempted and applied to the simulation of flameless combustion. Radiation is modeled using the spectral line-based weighted-sum-of-gray-gases approach to calculate gaseous radiative properties of combustion products using the correlation of the line-by-line spectra of H2O and CO2. The emissivity weights and absorption coefficients were optimized for a range of optical thicknesses and temperatures encountered in the considered furnace. Efforts were also made on the development of a reliable and detailed experimental dataset for validation. Measurements are performed in a low calorific value syngas furnace operating under flameless combustion. This test rig features a thermal charge which can extract about 60% of combustion heat release via 80% of radiative heat transfer, making it of special interest for modeling validation. The comparison between the simulation and the experiment demonstrated a fair prediction of heat transfer, energy balance, temperature, and chemical species fields.
APA, Harvard, Vancouver, ISO, and other styles
7

Hu, Xuanyu, Bastian Gundlach, Ingo von Borstel, Jürgen Blum, and Xian Shi. "Effect of radiative heat transfer in porous comet nuclei: case study of 67P/Churyumov-Gerasimenko." Astronomy & Astrophysics 630 (September 20, 2019): A5. http://dx.doi.org/10.1051/0004-6361/201834631.

Full text
Abstract:
Context. Radiative heat transfer occurs in a porous medium, such as regolith on planetary bodies. Radiation enhances the efficiency of heat transport through the subsurface, effecting a strong temperature dependence of thermal conductivity. However, this effect has been omitted in many studies of comet 67P/Churyumov-Gerasimenko (67P). Aims. We concisely review the method for characterizing radiative heat transfer and present a generic treatment in thermal modeling. In particular, we study the impact of radiative heat transfer on 67P subject to both diurnal and seasonal variations of insolation. Methods. We adapted a numerical model based on the Crank–Nicolson scheme to estimate the subsurface temperatures and water production rate of 67P, where conductivity may vary with depth. Results. Radiative heat transfer is efficient during the day near the surface but it dicreases at night, which means that more energy is deposited underneath the diurnal thermal skin. The effect increases with pore size and accordingly, with the size of the constituent aggregates of the nucleus. It also intensifies with decreasing heliocentric distance. Close to perihelion, within 2 au, for example, radiation may raise the temperature by more than 20 K at a depth of 5 cm, compared with a purely conductive nucleus. If the nucleus is desiccated and composed of centimeter-sized aggregates, the subsurface at 0.5 m may be warmed to above 180 K. Conclusions. Radiative heat transfer is not negligible if the nucleus of 67P consists of aggregates that measure millimeters or larger. To distinguish its role and ascertain the pore size of the subsurface, measurements of temperatures from a depth of ~1 cm down to several decimeters are most diagnostic. The water production rate of the nucleus, on the other hand, does not provide a useful constraint.
APA, Harvard, Vancouver, ISO, and other styles
8

Tong, T. W., and S. B. Sathe. "Heat Transfer Characteristics of Porous Radiant Burners." Journal of Heat Transfer 113, no. 2 (May 1, 1991): 423–28. http://dx.doi.org/10.1115/1.2910578.

Full text
Abstract:
This paper reports a numerical study of the heat transfer characteristics of porous radiant burners, which have significant advantages over conventional burners. The heat transfer characteristics are investigated using a one-dimensional conduction, convection, and radiation model. The combustion phenomenon is modeled as spatially dependent heat generation. Nonlocal thermal equilibrium between the gas and solid phases is accounted for by using separate energy equations for the two phases. The solid matrix is assumed to emit, absorb, and scatter radiant energy. The spherical harmonics approximation is used to solve the radiative transfer equation. The coupled energy equations and the radiative transfer equations are solved using a numerical iterative procedure. The effects of the various factors on the performance of porous radiant burners are determined. It is revealed that for a given rate of heat generation, large optical thicknesses and high heat transfer coefficients between the solid and gas phases are desirable for maximizing radiant output. Also, low solid thermal conductivities, scattering albedos and flow velocities, and high inlet environment reflectivities produced high radiant output.
APA, Harvard, Vancouver, ISO, and other styles
9

Fernandez Arroiabe, Peru, Jon Iturralde Iñarga, Mercedes Gómez de Arteche Botas, Susana López Pérez, Eduardo Ubieta Astigarraga, Iñigo Unamuno, Manex Martinez-Agirre, and M. Mounir Bou-Ali. "Design of a radiative heat recuperator for steel processes." MATEC Web of Conferences 330 (2020): 01034. http://dx.doi.org/10.1051/matecconf/202033001034.

Full text
Abstract:
In recent years, there has been an increasing interest in the recovery of the waste heat of steel and glass processes. This work proposes a numerical study of a waste heat exchanger system for steel production processes. The radiative energy is transferred to a commercial oil, which can be used to produce electricity. The behavior of the recuperator is analysed using a 3D numerical model, considering the constrains of a real production plant. The influence of the radiation properties of the materials on the temperature and heat transfer rate are also examined. The results show that the absorptivity of the tubes influences significantly the absorbed waste heat. Furthermore, heterogeneous mass flow distribution should be applied to optimize the total heat transfer rate.
APA, Harvard, Vancouver, ISO, and other styles
10

Vyas, Prashant Dineshbhai, Harish C. Thakur, and Veera P. Darji. "Nonlinear analysis of convective-radiative longitudinal fin of various profiles." International Journal of Numerical Methods for Heat & Fluid Flow 30, no. 6 (May 29, 2019): 3065–82. http://dx.doi.org/10.1108/hff-08-2018-0444.

Full text
Abstract:
Purpose This paper aims to study nonlinear heat transfer through a longitudinal fin of three different profiles. Design/methodology/approach A truly meshfree method is used to undertake a nonlinear analysis to predict temperature distribution and heat-transfer rate. Findings A longitudinal fin of three different profiles, such as rectangular, triangular and concave parabolic, are analyzed. Temperature variation, along with the fin length and rate of heat transfer in steady state, under convective and convective-radiative environments has been demonstrated and explained. Moving least square (MLS) approximants are used to approximate the unknown function of temperature T(x) with Th(x). Essential boundary conditions are imposed using the penalty method. An iterative predictor–corrector scheme is used to handle nonlinearity. Research limitations/implications Modelling fin in a convective-radiative environment removes the assumption of no radiation condition. It also allows to vary convective heat-transfer coefficient and predict the closer values to the real problems for the corresponding fin surfaces. Originality/value The meshless local Petrov–Galerkin method can solve nonlinear fin problems and predict an accurate solution.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Radiative Heat Transfer Rate"

1

Wangdhamkoom, Panitan. "Characteristics of multimode heat transfer in a differentially-heated horizontal rectangular duct." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/1007.

Full text
Abstract:
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 heating configurations: one uniform wall temperature (CS1) and two linearly varying wall temperature cases (CS2 and CS3) are analysed. The study considers the combined effects of natural convection, forced convection and radiation heat transfer on the overall heat transfer characteristics. Air, which is assumed to be a non-participating medium, is chosen as the working fluid. A computational fluid dynamics solver is used to solve a set of governing equations for a range of parameters.For chosen duct aspect ratios, the numerical model simulates the flow and heat transfer for two main effects: buoyancy and radiation heat transfer. Buoyancy effect is represented by Grashof number, which is varied from 2,000 to 1,000,000. The effect of radiation heat transfer is examined by choosing different wall surface emissivity values. The weak and strong radiation effect is represented by the emissivity values of 0.05 and 0.85 respectively. Three duct aspect ratios are considered - 0.5, 1 and 2. The heat transfer characteristics of all the above heating configurations - CS1, CS2, and CS3 are analysed and compared. The numerical results show that, for all heating configurations and duct aspect ratios, the overall heat transfer rate is enhanced when the buoyancy effect increases. Since buoyancy effect induces natural circulation, this circulation is therefore the main mechanism that enhances heat transfer. Radiation heat transfer is found to significantly influence convection heat transfer in high Grashof numbers.
APA, Harvard, Vancouver, ISO, and other styles
2

Wangdhamkoom, Panitan. "Characteristics of multimode heat transfer in a differentially-heated horizontal rectangular duct." Curtin University of Technology, Department of Mechanical Engineering, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=17353.

Full text
Abstract:
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 heating configurations: one uniform wall temperature (CS1) and two linearly varying wall temperature cases (CS2 and CS3) are analysed. The study considers the combined effects of natural convection, forced convection and radiation heat transfer on the overall heat transfer characteristics. Air, which is assumed to be a non-participating medium, is chosen as the working fluid. A computational fluid dynamics solver is used to solve a set of governing equations for a range of parameters.For chosen duct aspect ratios, the numerical model simulates the flow and heat transfer for two main effects: buoyancy and radiation heat transfer. Buoyancy effect is represented by Grashof number, which is varied from 2,000 to 1,000,000. The effect of radiation heat transfer is examined by choosing different wall surface emissivity values. The weak and strong radiation effect is represented by the emissivity values of 0.05 and 0.85 respectively. Three duct aspect ratios are considered - 0.5, 1 and 2. The heat transfer characteristics of all the above heating configurations - CS1, CS2, and CS3 are analysed and compared. The numerical results show that, for all heating configurations and duct aspect ratios, the overall heat transfer rate is enhanced when the buoyancy effect increases. Since buoyancy effect induces natural circulation, this circulation is therefore the main mechanism that enhances heat transfer. Radiation heat transfer is found to significantly influence convection heat transfer in high Grashof numbers.
APA, Harvard, Vancouver, ISO, and other styles
3

Maheria, Mehulkumar. "Thermal Analysis of Natural Convectiona and Radiation in Porous Fins." Cleveland State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=csu1281982835.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Colomer, Rey Guillem. "Numerical methods for radiative heat transfer." Doctoral thesis, Universitat Politècnica de Catalunya, 2006. http://hdl.handle.net/10803/6691.

Full text
Abstract:
L'objectiu principal d'aquesta tesi es l'estudi de la transferència d'energia per radiació. Per aquest motiu, s'ha estudiat la fenomenologia bàsica de la transferencia de calor per radiació. Tenint en compte el tipus d'equació que descriu aquesta transferència d'energia, aquesta tesi esta encarada als metodes numèrics que ens permetran incorporar la radiació en els nostres càlculs. Donat que aquest és el primer treball d'aquestes característiques en el grup de recerca CTTC ("Centre Tecnològic de Transferència de Calor"), està limitat a geometries senzilles, cartesianes i cilíndriques.

En el capítol 1 s'exposa una breu introducció a la transferència d'energia per radiació, i una explicació de les equacions que la governen. Es tracta de l'equació del transport radiatiu, formulada en termes dels coeficients d'absorció i de dispersió, i l'equació de l'energia. També s'indica quan cal tenir en compte aquest fenòmen, i a més a més, es defineixen totes les magnituds i conceptes que s'han utilitzat en aquesta tesi. També es dóna una breu descripció d'algunes simplificacions que es poden fer a les equacions governants.

El mètode de les radiositats s'explica en el capítol 2. També s'hi descriu un procediment numèric que permet calcular els factors de vista en geometries amb simetria cilíndrica, i es presenten resultats obtinguts amb el mètode descrit. Tot i que aquest capítol està una mica deslligat de la resta de la tesi, l'algoritme ideat per tractar geometries tridimensionals amb un temps computacional molt proper al de geometries bidimensionals, sense un increment de memòria apreciable, dóna uns resultats prou bons com per formar part de la tesi.

El mètode de les ordenades discretes (DOM) es detalla en el capítol 3. L'aspecte més important d'aquest mètode es l'elecció del conjunt d'ordenades per integrar l'equació del transport radiatiu. S'enumeren quines propietats han d'acomplir aquests conjunts. S'hi explica amb detall la discretització de la equació del transport radiatiu, tant en coordenades cartesianes com en cilíndriques. Es presenten també alguns resultats ilustratius obtinguts amb aquest mètode.

En el moment en que es vol resoldre un problema real, cal tenir present que el coeficients d'absorció pot dependre bruscament de la longitud d'ona de la radiació. En aquesta tesi s'ha considerat aquesta dependència amb especial interés, en el capítol 4. Aquest interès ha motivat una recerca bibliogràfica sobre la modelització aquesta forta dependència espectral del coeficient d'absorció. Aquesta recerca s'ha dirigit també a l'estudi dels diferents models numèrics existents capaços d'abordar-la, i de resoldre la equació del transport radiatiu en aquestes condicions. Es descriuen diversos mètodes, i, d'aquests, se n'han implementat dos: el mètode de la suma ponderada de gasos grisos (WSGG), i el mètode de la suma de gasos grisos ponderada per línies espectrals (SLW). S'hi presenten també resultats ilustratius.

S'han realitzat multitud de proves en el codi numèric resultant de l'elaboració d'aquesta tesi. Tenint en compte els resultats obtinguts, es pot dir que els objectius proposats a l'inici de la tesi s'han acomplert. Com a demostració de la utilitat del codi resultant, aquest ha estat integrat en un codi de proposit general (DPC), resultat del treball de molts investigadors en els darrers anys.

Aquesta esmentada integració permet la resolució de problemes combinats de transferència de calor, analitzats en els capítols 5 i 6, on la radiació s'acobla amb la transferència de calor per convecció. La influència de la radiació en la transferència total de calor s'estudia en el capítol 5, publicat a la International Journal of Heat and Mass Transfer, volum 47 (núm. 2), pàg. 257-269, 2004. En el capítol 6, s'analitza l'efecte d'alguns paràmetres del mètode SLW en un problema combinat de transferència de calor. Aquest capítol s'ha enviat a la revista Journal of Quantitative Spectroscopy and Radiative Transfer, per què en consideri la publicació.
The main objective of the present thesis is to study the energy transfer by means of radiation. Therefore, the basic phenomenology of radiative heat transfer has been studied. However, considering the nature of the equation that describes such energy transfer, this work is focussed on the numerical methods which will allow us to take radiation into account, for both transparent and participating media. Being this the first effort within the CTTC ("Centre Tecnològic de Transferència de Calor") research group on this subject, it is limited to simple cartesian and cylindrical geometries.

For this purpose, chapter 1 contains an introduction to radiative energy transfer and the basic equations that govern radiative transfer are discussed. These are the radiative transfer equation, formulated in terms of the absorption and scattering coefficients, and the energy equation. It is also given a discussion on when this mode of energy transfer should be considered. In this chapter are also defined all of the magnitudes and concepts used throughout this work. It ends with a brief description of some approximate methods to take radiation into account.

The Radiosity Irradiosity Method is introduced in chapter 2. In this chapter it is also described a numerical method to calculate the view factors for axial symmetric geometries. The main results obtained in such geometries are also presented. Although a little disconnected from the rest of the present thesis, the algorithm used to handle "de facto"' three dimensional geometries with computation time just a little longer than two dimensional cases, with no additional memory consumption, is considered worthy enough to be included in this work.

In chapter 3, the Discrete Ordinates Method (DOM) is detailed. The fundamental aspect of this method is the choice of an ordinate set to integrate the radiative transfer equation. The characterization of such valuable ordinate sets is laid out properly. The discretization of the radiative transfer equation is explained in etail. The direct solution procedure is also outlined. Finally, illustrative results obtained with the DOM under several conditions are presented.

In the moment we wish to solve real problems, we face the fact that the absorption and scattering coefficients depend strongly on radiation wavelength. In the present thesis, special emphasis has been placed on studying the radiative properties of real gases in chapter 4. This interest resulted on a bibliographical research on how the wavenumber dependence of the absorption coefficient is modeled and estimated. Furthermore, this bibliographical research was focussed also on numerical models able to handle such wavenumber dependence. Several methods are discussed, and two of them, namely the Weighted Sum of Gray Gases (WSGG) and the Spectral Line Weighted sum of gray gases (SLW), have been implemented to perform non gray calculations. Some significant results are shown.

Plenty of tests have been performed to the numerical code that resulted from the elaboration of this thesis. According to the results obtained, the objectives proposed in this thesis have been satisfied. As a demonstration of the usefulness of the implemented code, it has been succesfully integrated to a general purpose computational fluid dynamics code (DPC), fruit of the effort of many researchers during many years.
Results of the above integration lead to the resolution of combined heat transfer problems, that are analyzed in chapters 5 and 6, where radiative heat transfer is coupled to convection heat transfer. The effect of radiation on the total heat transfer is studied in chapter 5, which has been published as International Journal of Heat and Mass Transfer, volume 47 (issue 2), pages 257--269, year 2004. In chapter 6, the impact of some parameters of the SLW model on a combined heat transfer problem is analyzed. This chapter has been submitted for publication at the Journal of Quantitative Spectroscopy and Radiative Transfer.
APA, Harvard, Vancouver, ISO, and other styles
5

Ramamoorthy, Babila. "Numerical simulation of radiative heat transfer." Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2009r/ramamoorthy.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Quintero, de la Garza Rodrigo Javier 1974. "Spheroidization of iron powders by radiative heat transfer." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85328.

Full text
Abstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.
Includes bibliographical references (leaves 45-46).
by Rodrigo Javier Quintero de la Garza.
S.M.
APA, Harvard, Vancouver, ISO, and other styles
7

Dai, Jin. "Near-Field Radiative Heat Transfer between Plasmonic Nanostructures." Doctoral thesis, KTH, Optik och Fotonik, OFO, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-195653.

Full text
Abstract:
Radiative heat transfer (RHT) due to coupled electromagnetic near field scan significantly exceed that dictated by Planck’s law. Understanding such phenomenon is not only of fundamental scientific interest, but also relevant to a broad range of applications especially connected to nanotechnologies.This dissertation elaborates, through a scattering approach based on the rigorous coupled wave analysis method, how plasmonic nanostructures can tame the near-field RHT between two bodies. The transmission-factor spectra are corroborated by photonic band diagrams computed using a finite element method. The main work begins by showing that the phenomenon of spoofsurface plasmon polariton (SSPP) guided on grooved metal surfaces can play a similar role as surface phonon polariton in enhancing the RHT between two closely placed plates. Since dispersions of SSPPs especially their resonance frequencies can be engineered through geometrical surface profiling,one has great freedom in tailoring spectral properties of near-field RHT. Further enhancement of RHT can be achieved through techniques like filling of dielectrics in grooves or deploying supercells. A thorough study of RHT betweentwo 1D or 2D grooved metal plates confirms super-Planckian RHT at near-field limit, with 2D grooved metal plates exhibiting a superior frequency selectivity. We also present RHT with a more exotic type of plasmonic nanostructures consisting of profile-patterned hyperbolic metamaterial arrays, and show that with such plasmonic nanostructures one can achieve an ultrabroadband super-Planckian RHT.

QC 20161111

APA, Harvard, Vancouver, ISO, and other styles
8

Luo, Gang. "A cloud fraction and radiative transfer model." Diss., Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/25753.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Safdari, Mohammad Saeed. "Characterization of Pyrolysis Products from Fast Pyrolysis of Live and Dead Vegetation." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/8807.

Full text
Abstract:
Wildland fire, which includes both planned (prescribed fire) and unplanned (wildfire) fires, is an important component of many ecosystems. Prescribed burning (controlled burning) is used as an effective tool in managing a variety of ecosystems in the United States to reduce accumulation of hazardous fuels, manage wildlife habitats, mimic natural fire occurrence, manage traditional native foods, and provide other ecological and societal benefits. During wildland fires, both live and dead (biomass) plants undergo a two-step thermal degradation process (pyrolysis and combustion) when exposed to high temperatures. Pyrolysis is the thermal decomposition of organic material, which does not require the presence of oxygen. Pyrolysis products may later react with oxygen at high temperatures, and form flames in the presence of an ignition source. In order to improve prescribed fire application, accomplish desired fire effects, and limit potential runaway fires, an improved understanding of the fundamental processes related to the pyrolysis and ignition of heterogeneous fuel beds of live and dead plants is needed.In this research, fast pyrolysis of 14 plant species native to the forests of the southern United States has been studied using a flat-flame burner (FFB) apparatus. The results of fast pyrolysis experiments were then compared to the results of slow pyrolysis experiments. The plant species were selected, which represent a range of common plants in the region where the prescribed burning has been performed. The fast pyrolysis experiments were performed on both live and dead (biomass) plants using three heating modes: (1) convection-only, where the FFB apparatus was operated at a high heating rate of 180 °C s-1 (convective heat flux of 100 kW m-2) and a maximum fuel surface temperature of 750 °C; (2) radiation-only, where the plants were pyrolyzed under a moderate heating rate of 4 °C s-1 (radiative heat flux of 50 kW m-2), and (3) a combination of radiation and convection, where the plants were exposed to both convective and radiative heat transfer mechanisms. During the experiments, pyrolysis products were collected and analyzed using a gas chromatograph equipped with a mass spectrometer (GC-MS) for the analysis of tars and a gas chromatograph equipped with a thermal conductivity detector (GC-TCD) for the analysis of light gases.The results showed that pyrolysis temperature, heating rate, and fuel type, have significant impacts on the yields and the compositions of pyrolysis products. These experiments were part of a large project to determine heat release rates and model reactions that occur during slow and fast pyrolysis of live and dead vegetation. Understanding the reactions that occur during pyrolysis then can be used to develop more accurate models, improve the prediction of the conditions of prescribed burning, and improve the prediction of fire propagation.
APA, Harvard, Vancouver, ISO, and other styles
10

End, Thomas [Verfasser]. "Optimal Control of Nonlocal Radiative Heat Transfer / Thomas End." München : Verlag Dr. Hut, 2012. http://d-nb.info/1021072893/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Radiative Heat Transfer Rate"

1

United States. National Aeronautics and Space Administration., ed. Nickel-hydrogen battery state of charge during low rate trickle charging. [Washington, DC: National Aeronautics and Space Administration, 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

United States. National Aeronautics and Space Administration., ed. Nickel-hydrogen battery state of charge during low rate trickle charging. [Washington, DC: National Aeronautics and Space Administration, 1995.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Radiative heat transfer. 2nd ed. Amsterdam: Academic Press, 2003.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Radiative heat transfer. New York: McGraw-Hill, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Modest, Michael M. Radiative heat transfer. Maidenhead: McGraw-Hill, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Thermal radiative transfer and properties. New York: Wiley, 1992.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Yadav, Rahul, C. Balaji, and S. P. Venkateshan. Radiative Heat Transfer in Participating Media. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-030-99045-9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Modest, Michael F., and Daniel C. Haworth. Radiative Heat Transfer in Turbulent Combustion Systems. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-27291-7.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

F, Nogotov E., and Trofimov V. P, eds. Radiative heat transfer in two-phase media. Boca Raton, Fla: CRC Press, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Radiative transfer in nontransparent, dispersed media. Berlin: Springer-Verlag, 1988.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Radiative Heat Transfer Rate"

1

Smoot, L. Douglas, and Philip J. Smith. "Radiative Heat Transfer." In Coal Combustion and Gasification, 349–71. Boston, MA: Springer US, 1985. http://dx.doi.org/10.1007/978-1-4757-9721-3_14.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Volokitin, Aleksandr I., and Bo N. J. Persson. "Radiative Heat Transfer." In Electromagnetic Fluctuations at the Nanoscale, 91–121. Berlin, Heidelberg: Springer Berlin Heidelberg, 2017. http://dx.doi.org/10.1007/978-3-662-53474-8_6.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Akimoto, Hajime, Yoshinari Anoda, Kazuyuki Takase, Hiroyuki Yoshida, and Hidesada Tamai. "Radiative Heat Transfer." In An Advanced Course in Nuclear Engineering, 361–74. Tokyo: Springer Japan, 2016. http://dx.doi.org/10.1007/978-4-431-55603-9_18.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Shang, Joseph J. S. "Radiative Heat Transfer." In Classic and High-Enthalpy Hypersonic Flows, 237–66. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9781003212362-13.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Campbell-Lochrie, Zakary, Carlos Walker-Ravena, Michael Gallagher, Nicholas Skowronski, Eric V. Mueller, and Rory M. Hadden. "Effect of Fuel Bed Structure on the Controlling Heat Transfer Mechanisms in Quiescent Porous Flame Spread." In Advances in Forest Fire Research 2022, 1443–48. Imprensa da Universidade de Coimbra, 2022. http://dx.doi.org/10.14195/978-989-26-2298-9_219.

Full text
Abstract:
The increasing importance of prescribed fire use has led to an increased focus on the development of modelling tools suited to conditions typical of prescribed fire scenarios. An improved understanding of flame spread through porous surface fuels represents an important part of these efforts. In the lower wind speed conditions typical of many prescribed burns, the role of fuel structure may be of greater importance than in highly wind-aided flame spread scenarios. The porous nature of wildland fuel beds complicates efforts to apply existing, solid surface theories for flame spread in low or quiescent wind conditions as radiation, convection and conduction may all occur within the porous fuel in addition to flame heating. An important first step in the development of any flame spread theory is the identification of the dominant heat transfer mechanisms but for wildland fuels the effect of fuel structure on the relative importance of different heating mechanisms must be considered. To investigate the role of fuel structure we therefore present a series of laboratory-based flame spread experiments conducted in pine needle fuel beds with various structural properties. The fuel loading and bulk density were independently varied by controlling the fuel bed height with water-cooled heat flux gauges used to measure the (radiant and total) heat flux from both the above-bed flame and the in-bed combustion region. A single dimensionless parameter (ασδ), incorporating the fuel bed porosity (α), fuel element surface-to-volume ratio (σ), and fuel bed height (δ), was used to describe the overall fuel bed structure. The heat flux measurements highlighted the dominant role of in-bed heating across all of the studied fuel conditions although the magnitude of above-bed flame heating increased with increasing fuel loading. Heat fluxes from the in-bed combustion region exceeded those from the above-bed flame region with the magnitude of the peak (radiant and total) heat flux at each measurement location generally increasing with increasing ασδ across the studied range (ασδ=49 to 399). However, the effect of fuel loading was also apparent with a positive relationship also observed between fuel loading and flame height. The experimentally observed effective heating distances also varied with bulk density and fuel loading and were used to evaluate the use of a thermal modelling approach incorporating the bulk structural properties of the porous fuel bed. Comparison with experimental observations of spread rate indicated a maximum variation in predicted spread rate of 29 % where only radiative transfer from the in-bed combustion region was considered, with closer agreement at lower ασδ values. Where the contributions of both the in-bed and above-bed heat transfer mechanisms were considered, the need to incorporate additional heat loss terms into this thermal model were apparent. This study therefore emphasises the important role of porous fuel structure on the in-bed heat transfer and assesses suitable, physically meaningful structural descriptors. The experiments presented in this study will also provide a valuable dataset for future model development efforts incorporating measurements of fire behaviour and underlying physical phenomena across a wide range of structural conditions.
APA, Harvard, Vancouver, ISO, and other styles
6

Steane, Andrew M. "Radiative heat transfer." In Thermodynamics, 291–98. Oxford University Press, 2016. http://dx.doi.org/10.1093/acprof:oso/9780198788560.003.0020.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

"Radiative Heat Transfer." In Heat Transfer in Single and Multiphase Systems, 191–244. CRC Press, 2002. http://dx.doi.org/10.1201/9781420041064-8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

"Radiative Heat Transfer." In Mechanical Engineering Series, 171–224. CRC Press, 2002. http://dx.doi.org/10.1201/9781420041064.ch4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Kobayashi, Shiro, Soo-Ik Oh, and Taylan Altan. "Thermo-Viscoplastic Analysis." In Metal Forming and the Finite-Element Method. Oxford University Press, 1989. http://dx.doi.org/10.1093/oso/9780195044027.003.0015.

Full text
Abstract:
The main concern here is the analysis of plastic deformation processes in the warm and hot forming regimes. When deformation takes place at high temperatures, material properties can vary considerably with temperature. Heat is generated during a metal-forming process, and if dies are at a considerably lower temperature than the workpiece, the heat loss by conduction to the dies and by radiation and convection to the environment can result in severe temperature gradients within the workpiece. Thus, the consideration of temperature effects in the analysis of metal-forming problems is very important. Furthermore, at elevated temperatures, plastic deformation can induce phase transformations and alterations in grain structures that, in turn, can modify the flow stress of the workpiece material as well as other mechanical properties. Since materials at elevated temperatures are usually rate-sensitive, a complete analysis of hot forming requires two considerations—the effect of the rate-sensitivity of materials and the coupling of the metal flow and heat transfer analyses. A material behavior that exhibits rate sensitivity is called viscoplastic. A theory that deals with viscoplasticity was described in Chap. 4. It was shown that the governing equations for deformation of viscoplastic materials are formally identical to those of plastic materials, except that the effective stress is a function of strain, strain-rate, and temperature. The application of the finite-element method to the analysis of metal-forming processes using rigid-plastic materials leads to a simple extension of the method to rigid-viscoplastic materials. The importance of temperature calculations during a metal-forming process has been recognized for a long time. Until recently, the majority of the work had been based on procedures that uncouple the problem of heat transfer from the metal deformation problem. Several researchers have used the following approach. They determined the flow velocity fields in the problem either experimentally or by calculations, and they then used these fields to calculate heat generation. Examples of this approach are the works of Johnson and Kudo on extrusion, and of Tay et al. on machining. Another approach uses Bishop’s numerical method in which heat generation and transportation are considered to occur instantaneously for each time-step with conduction taking place during the time-step.
APA, Harvard, Vancouver, ISO, and other styles
10

Modest, Michael F. "Nanoscale Radiative Transfer." In Radiative Heat Transfer, 803–17. Elsevier, 2013. http://dx.doi.org/10.1016/b978-0-12-386944-9.50024-8.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Radiative Heat Transfer Rate"

1

Chang, S. S., H. H. Chiu, and T. S. Lee. "Droplet Combustion With Radiative Heat Transfer." In ASME 1997 Turbo Asia Conference. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/97-aa-144.

Full text
Abstract:
Combustion of a droplet, either in stationary or convective motion under the effect of radiative heat transfer is studied. The closed form expression of gasification laws and the radiative flux distribution surrounding a stationary droplet are calculated using Potential Theory of Radiation in conjunction with the canonical theory of droplet recently developed. Various mechanisms contributing to gasification rate of a combusting droplet under radiative condition are determined by the Canonical Integral Method to assess their importance. It is found that radiation effect plays an important role when the droplet considered is of large size and under high environmental temperature. It is seen from the present study that for a typical application in turbine combustor, the enhancement of droplet combustion rate due to radiation ranges from 5 percents to 15 percents depending on the droplet size and the environmental conditions.
APA, Harvard, Vancouver, ISO, and other styles
2

He, Zhen-Zong, Hong Qi, Qin Chen, Ya-Tao Ren, and Li-Ming Ruan. "Effect of Fractal-Like Aggregation on Radiative Properties and Specific Growth Rate of Chlorella." In The 15th International Heat Transfer Conference. Connecticut: Begellhouse, 2014. http://dx.doi.org/10.1615/ihtc15.rad.009531.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Wang, Jingfu, and Guoqiang Li. "Analysis of Radiation Reabsorption Effects on Flame Characteristics and NOx Emission in Laminar Flames." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-23061.

Full text
Abstract:
The radiation reabsorption effects on NOx formation and flame characteristics in CH4/Air laminar flames were numerically investigated by using full chemistry mechanism and detailed transport properties. The radiative gases were treated as non-gray gas and their spectral radiative properties were evaluated by means of the statistical narrow-band model. The radiative heat transfer equation was solved by the discrete ordinate method. It was found that the reabsorption of emitting radiation leads to substantially wider flame thickness and higher flame temperature than those calculated by using the optically thin model, and the radiation reabsorption effect on the “radiation extinction limit” becomes more important. The results show that the level of NOx is predicted to be highest in the adiabatic flames, that is, flames without radiation heat loss, and that the level of NOx is predicted to be lowest in the flames by the optically thin model. In the flames by the SNB model, the predicted amount of NOx lies between these two levels. The calculated results also show that the radiation reabsorption effect on NOx formation grows stronger as the stretch rate decreases, particularly when CO2, a strong absorber, is added to the unburned gas mixture. In this study, the effectiveness and validity of the optically thin radiation model for calculating NOx formation in laminar flames was also investigated in comparison with the SNB model.
APA, Harvard, Vancouver, ISO, and other styles
4

Yan, Wei-Mon, and Kuan-Tzong Lee. "Natural Convection Heat Transfer in a Vertical Square Duct With Radiation Effects." In ASME 1999 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1999. http://dx.doi.org/10.1115/imece1999-0972.

Full text
Abstract:
Abstract The present work investigates numerically the natural convection heat transfer with radiation effects in an open vertical square duct. The integro-differential radiative transfer equation is solved by discrete ordinates method. The vorticity-velocity formulation is applied to solve for the coupled momentum and energy equations. The effects of five major parameters, Grashof number Gr, conduction-to-radiation parameter Nc, optical thickness τ, single scattering albedo ω and temperature ratio Tr, on the combined natural and radiation heat transfer are discussed in detail. The numerical results of the dimensionless induced volume flow rate and average Nusselt numbers show that the thermal radiation would enhance the heat transfer rate. Additionally, the variations of the induced volume flow rate and total Nusselt number are independent of radiative parameters under fully-developed flow limit.
APA, Harvard, Vancouver, ISO, and other styles
5

Archibold, Antonio Ramos, Muhammad M. Rahman, D. Yogi Goswami, and Elias L. Stefanakos. "High Temperature Latent-Heat Thermal Energy Storage Module With Enhanced Combined Mode Heat Transfer." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-38766.

Full text
Abstract:
A numerical solution of the melting problem of a semitransparent gray, medium contained in a closed heated spherical shell is presented in this study. The influence of all the fundamental energy transfer mechanisms on the melting dynamics of the phase change medium (PCM) has been analyzed, in order to extend the convectional natural convection-dominated model and to expand the limited literature in the thermal energy storage (TES) area at high operating temperatures (>800°C). A two-dimensional, axisymmetric, transient model has been solved numerically. The discrete ordinate method was used to solve the equation of radiative transfer and the finite volume scheme was used to solve the equations for mass, momentum and energy conservation. The effect of the optical thickness of the medium on the melt fraction rate, total and radiative heat transfer rates at the inner surface of the shell has been analyzed and discussed. Also the influence of thermal radiation has been quantified by performing comparisons between the pure conduction and the simultaneous conduction and radiation models. The results showed that the presence of thermal radiation enhances the melting process, particularly during the solid phase sensible heating process in the multi-mode heat transfer model. Also, it was found that the contribution of the radiant energy exchange is one order of magnitude smaller than the convective transport process.
APA, Harvard, Vancouver, ISO, and other styles
6

Viskanta, R. "Overview of Radiative Transfer in Cellular Porous Materials." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88648.

Full text
Abstract:
Highly porous cellular materials capable of absorbing, emitting and scattering radiation are finding use at low and high temperatures in a range of traditional and modern technologies. The motivation for use of cellular materials is attributed to the high volumetric heat transfer rate (i.e., large surface area to volume ratio, high volumetric heat transfer coefficient), and large mixing rate due to the tortuosity of open cell foams. A brief overview of simulating heat transfer in cellular materials is presented and most important modeling parameters are identified, but the focus of the discussion is on heat transfer in cellular materials in the presence of radiation environment. Several examples involving radiation, conduction and radiation as well as convection and radiation for different technological applications are discussed, and the models are assessed by comparing the predictions with experimental data.
APA, Harvard, Vancouver, ISO, and other styles
7

Srinivasa Ramanujam, K., and C. Balaji. "A Fast Polarized Microwave Radiative Transfer Model for a Raining Atmosphere." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22228.

Full text
Abstract:
Retrieval of vertical rain structure and hence the estimation of surface rain rate is of central importance to various missions involving remote sensing of the earth’s atmosphere. Typically, remote sensing involves scanning the earth’s atmosphere at visible, infra red and microwave frequencies. While the visible and infra red frequencies can scan the atmosphere with higher spatial resolution, they are not suited for scanning under cloudy conditions as clouds are opaque under these frequencies. However, the longer wavelength microwave radiation can partially penetrate through the clouds without much attenuation thereby making it more suitable for meteorological purposes. The retrieval algorithms used for passive microwave remote sensing involve modeling of the radiation in the earth’s atmosphere where in the clouds and precipitating rain (also known as hydrometeors) emit / absorb / scatter. Additionally, it has been observed that the rain droplets tend to polarize the microwave signal emitted by the earth’s surface. In view of this, the first step in the development of a rainfall retrieval algorithm for any satellite mission is to simulate the radiances (also known as brightness temperatures) that would have been measured by a typical radiometer for different sensor frequencies and resolutions. Towards this, a polarized microwave radiation transfer code has been developed in house for a plane parallel raining atmosphere (henceforth called as forward model) that depicts the physics as seen by a satellite. Physics based retrieval algorithm often involves repeated execution of the forward model for various raining scenario. However, due to the complexity involved in the radiation modeling of the raining atmosphere which is participating in nature, the forward model suffers from the drawback that it requires enormous computational effort. In the present work, a much quicker alternative is proposed wherein the forward model can be replaced with an Artificial Neural Network (ANN) based Fast Forward Model (AFFM). This AFFM can be used in conjunction with an appropriate inverse technique to retrieve the rain structure. Spectral microwave brightness temperatures at frequencies corresponding to the Tropical Rainfall Measuring Mission (TRMM) of National Aeronautics and Space Administration (NASA) and Japan Aerospace Exploration Agency (JAXA) are first simulated using an in-house polarized radiate on transfer code for sixteen past cyclones in the North Indian Ocean region in the period (2000–2005), using the hydrometeor profiles retrieved from the Goddard Profiling Algorithm (GPROF) of the Tropical Rainfall Measuring Mission (TRMM)’s Microwave Imager (TMI). This data is split into two sets: while the first set of data is used for training the network, the remainder of the data is used for testing the ANN. The results obtained are very encouraging and shows that neural network is capable of predicting the brightness temperature accurately with the correlation coefficient of over 99%. Furthermore, the execution of the forward model on an Intel Core 2 Quad 3.0 GHz processor based, 8 GB DDR3 RAM workstation took 3 days, while the AFFM delivers the results in 10 seconds.
APA, Harvard, Vancouver, ISO, and other styles
8

Conceição, Eusébio, João Gomes, Maria Manuela Lúcio, Domingos Viegas, and Teresa Viegas. "Heat Transfer in a Pine Tree Trunk." In 8th International Conference on Human Interaction and Emerging Technologies. AHFE International, 2022. http://dx.doi.org/10.54941/ahfe1002775.

Full text
Abstract:
This article presents a numerical study on the heat and mass transfer in a pine trunk under the effect of a forest fire. The numerical model of the pine trunk is based on energy balance integral and differential equations. The virtual trunk geometry was developed using grid generation. The radiation heat exchanges are evaluated between the pine trunk and the plan surface of the front fire. These radiative exchanges are evaluated using view factors considering the grid generation in the tree and front fire. A fire front propagation at a constant fire spread rate of 0.01 m/s and a flame temperature of 500ºC were considered in this study. The field temperature evolution in the external surface and inside the pine trunk was obtained considering wind speed fluctuations with three different frequencies. In general, pine trunk temperatures increase with decreasing frequency of wind speed fluctuations.
APA, Harvard, Vancouver, ISO, and other styles
9

Seytier, Charline, and Mohammad H. Naraghi. "Combined Convective-Radiative Thermal Analysis of Inclined Roof Top Solar Chimney." In ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/es2011-54043.

Full text
Abstract:
A model for the combined spectral radiative and convective heat transfer analysis of solar chimneys is developed. The radiation part of this model is based on the spectral distribution of the solar heat flux and spectral radiative properties solar chimney components. Two methods are used for the convective part of this model, empirical correlations and a CFD analysis. The empirical correlations consist of stack effect correlation for air flow motion and convective heat transfer correlation for heat transfer coefficient calculations. The empirical correlations were used to obtain an initial estimation of surface temperatures which were then used in a CFD model to determine an improved estimation of the heat transfer coefficients and flow rates. By iterating between the spectral radiative and CFD models a converged value for the solar chimney flow rate and its thermal characteristics is obtained. The model is used to predict the volume flow rate of air moved for various configurations of solar chimneys (slopes and air gap distance).
APA, Harvard, Vancouver, ISO, and other styles
10

Baikin, Mordechai, Yehuda Taitel, and Dvora Barnea. "Flow Rate Maldistribution in Multi Heated Parallel Pipes." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22650.

Full text
Abstract:
Fluids flowing in parallel pipes, undergoing evaporation, take place in heat exchangers, boilers, power plants, cooling systems and in the nuclear industry. Evaporating two-phase flow in parallel micro-channels is considered for heat removal in microelectronic devices. The main motivation of the present work is associated with the use of solar energy collected in long lines. In this technology, an array of parallel pipes is located at the focal center of parabolic mirrors that focus solar radiation on the pipes to generate steam. It is a common knowledge that maldistribution may occur in evaporating liquid flowing in parallel pipes with common inlet and outlet manifolds. This phenomenon occurs due to multiple steady state solutions some of which are unstable. One may obtain uneven flow rate distribution even for the case of equal heating of the pipes. For non equal heating higher flow rates may take place in the less heated pipes. This is quite an unfavorable phenomenon. The theoretical model developed by Minzer et al. [1] for the flow rate distribution is extended to a larger number of pipes and different heating conditions. Stable and unstable solutions are identified and the model predictions are experimentally validated for different configurations involving three pipes. It is shown that the behavior of the system may depend on the history of the process exhibiting a hysteresis phenomenon. Transient simulations are carried out using this model in order to study the time dependent system response to finite disturbances and to changes in operational conditions.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Radiative Heat Transfer Rate"

1

Hayes, Steven Lowe. Radiative heat transfer in porous uranium dioxide. Office of Scientific and Technical Information (OSTI), December 1992. http://dx.doi.org/10.2172/10189532.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Tencer, John, Kevin Thomas Carlberg, Marvin E. Larsen, and Roy E. Hogan. Advanced Computational Methods for Thermal Radiative Heat Transfer. Office of Scientific and Technical Information (OSTI), October 2016. http://dx.doi.org/10.2172/1330205.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Schock, Alfred, and M. J. Abbate. Comparison of Methods for Calculating Radiative Heat Transfer. Office of Scientific and Technical Information (OSTI), January 2012. http://dx.doi.org/10.2172/1033384.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Fuchs, Marcel, Ishaiah Segal, Ehude Dayan, and K. Jordan. Improving Greenhouse Microclimate Control with the Help of Plant Temperature Measurements. United States Department of Agriculture, May 1995. http://dx.doi.org/10.32747/1995.7604930.bard.

Full text
Abstract:
A model of the energy balance of a transpiring crop in a greenhouse was developed in a format suitable for use in climate control algorithms aimed at dissipating excess heat during the warm periods. The model's parameters use external climatic variables as input. It incorporates radiation and convective transfer functions related to the operation of control devices like shading screens, vents, fans and enhanced evaporative cooling devices. The model identified the leaf boundary-layer resistance and the leaf stomatal and cuticular resistance as critical parameters regulating the temperature of the foliage. Special experiments evaluated these variables and established their relation to environmental factors. The research established that for heat load conditions in Mediterranean and arid climates transpiring crops maintained their foliage temperature within the range allowing high productivity. Results specify that a water supply ensuring minimum leaf resistance to remain below 100 s m-1, and a ventilation rate of 30 air exchanges per hour, are the conditions needed to achieve self cooling. Two vegetable crops, tomato and sweet pepper fulfilled maintained their leaf resistance within the prescribed range at maturity, i.e., during the critical warm season. The research evaluates the effects of additional cooling obtained from wet pad systems and spray wetting of foliage.
APA, Harvard, Vancouver, ISO, and other styles
5

Forney, Glenn P. Computing radiative heat transfer occurring in a zone fire model. Gaithersburg, MD: National Institute of Standards and Technology, 1991. http://dx.doi.org/10.6028/nist.ir.4709.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Ahluwalia, R. K., and K. H. Im. Spectral radiative heat transfer in coal furnaces using a hybrid technique. Office of Scientific and Technical Information (OSTI), March 1994. http://dx.doi.org/10.2172/10133030.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Ahluwalia, R., and K. Im. FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces. Office of Scientific and Technical Information (OSTI), August 1992. http://dx.doi.org/10.2172/6810345.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Ahluwalia, R. K., and K. H. Im. FURN3D: A computer code for radiative heat transfer in pulverized coal furnaces. Office of Scientific and Technical Information (OSTI), August 1992. http://dx.doi.org/10.2172/10125191.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Kirsch, Jared, and Joshua Hubbard. Complementary Study of Radiative Heat Transfer and Flow Physics from Moderate-scale Hydrocarbon Pool Fire Simulations. Office of Scientific and Technical Information (OSTI), November 2021. http://dx.doi.org/10.2172/1832312.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Skimmons, J. Determing the Radiative Heat Transfer out of the Fireball of an Atmospheric Nuclear Detonation using Experimental Data. Office of Scientific and Technical Information (OSTI), March 2020. http://dx.doi.org/10.2172/1603242.

Full text
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography