Thermal radiation properties

Tien, C.L. Thermal Radiation Properties of Gases in Hartnett, J.P. and Irvine, T.F., eds Advances in Heat Transfer. Volume 5 (Academic Press. New York. 1968)... 

When a solid is exposed to a thermal environment, it will either absorb or release heat. This thermal energy is delivered via heat transfer mechanisms of conduction, convection, and radiation. Typical thermal properties of a solid include specific heat, thermal conductivity, thermal expansion, and thermal radiation properties. 

G. G. GubarefF, J. E. Janssen, and R. H. Torberg, Thermal Radiation Properties Survey, Second ed., Honeywell Research Center, Minneapolis, MN (1960). 

Gubareff, G. G., J. E. Janssen, and R. H. Torborg Thermal Radiation Properties Survey, 2d ed., Minneapolis Honeywell Regulator Co., Minneapolis, Minn., 1960. Threlkeld, J. L., and R. C. Jordan Direct Solar Radiation Available on Clear Days, ASHAE Trans., vol. 64, pp. 45-56, 1958. 

D. Doermann and J. F. Sacadura, Thermal Radiation Properties of Dispersed Media Theoretical Prediction and Experimental Characterization, Radiative Transfer—II Proceedings of the Second International Symposium on Radiative Transfer, M. P. Mengtt (ed.), Begell House, New York, 1998 (in press). 

Wood, W.D., Deem, H. W. and Lucks, C. F. Thermal Radiation Properties (Plenum Press, New York, 1964)... 

Gubareff, G.G., Jansson, J.E., Torberg, R.H. Thermal Radiation Properties Survey, in Orisik, M.N. p. 103, Radiative Transfer, Wiley-Interscience, 1973. 

THERMAL RADIATION PROPERTIES OF SOME POLYMER BALLOON... 

THE DOUBLE-BEAM METHOD OF DETERMINING THE THERMAL RADIATION PROPERTIES OF DIFFUSING MATERIALS. 

The specimen is initially in thermal equilibrium with the surroundings, which are kept at room temperature. A continuous current is then supplied to the specimen, and measurements of potential difference, current, and temperature are continuously recorded versus time during the heating, giving a heat capacity versus temperature curve for the whole of the range covered. For example, Cezairliyan et measured the heat capacity of molybdenum between 1900 and 2800 K, as well as its electrical resistivity and thermal radiation properties. 

Blackbody Radiation Engineering calculations of thermal radiation from surfaces are best keyed to the radiation characteristics of the blackbody, or ideal radiator. The characteristic properties of a blackbody are that it absorbs all the radiation incident on its surface and that the quality and intensity of the radiation it emits are completely determined by its temperature. The total radiative fliix throughout a hemisphere from a black surface of area A and absolute temperature T is given by the Stefan-Boltzmann law ... 

Impact of release on people, property, or environment thermal radiation... 

Siegel, R. and Howell, J. R. Thermal Radiation Heat Transfer, 2nd edn (McGraw-Hill, New York, 1981) Sparrow, E. M. and Cess, R. D. Radiation Heat Transfer (Hemisphere Publishing, New York, 1978) Taylor, M. (ed.). Plate-fin Heat Exchangers Guide to their Specification and Use (HTFS, Harwell, 1987). Tohloukian, Y. S. Thermophvsical Properties of High Temperature Solid Materials (Macmillan, New York. 1967)... 

We still need to consider the coherence properties of astronomical sources. The vast majority of sources in the optical spectral regime are thermal radiators. Here, the emission processes are uncorrelated at the atomic level, and the source can be assumed incoherent, i. e., J12 = A /tt T(ri) (r2 — ri), where ()(r) denotes the Dirac distribution. In short, the general source can be decomposed into a set of incoherent point sources, each of which produces a fringe pattern in the Young s interferometer, weighted by its intensity, and shifted to a position according to its position in the sky. Since the sources are incoherent. 

Radiosity J Total thermal radiation energy leaving a surface (emitted and reflected) per unit time per unit area of energy transfer per unit area). The three terms, Absorptivity (a), Reflectivity (p), and Transmissivity (x), are all surface properties... 

Properties of peroxide cross-linked polyethylene foams manufactured by a nitrogen solution process, were examined for thermal conductivity, cellular structure and matrix polymer morphology. Theoretical models were used to determine the relative contributions of each heat transfer mechanism to the total thermal conductivity. Thermal radiation was found to contribute some 22-34% of the total and this was related to the foam s mean cell structure and the presence of any carbon black filler. There was no clear trend of thermal conductivity with density, but mainly by cell size. 27 refs. 

The polymers produced by thermal, radiation and plasma polymerization methods were among the first organic materials with semiconducting properties [97-99]. References to the early papers on photoconductivity in such materials may be found in the monograph [14]. 

To evaluate the thermodynamic and radiation properties of a natural or perturbed state of the upper atmosphere or ionosphere, the thermal and transport properties of heated air are required. Such properties are also of particular interest in plasma physics, in gas laser systems, and in basic studies of airglow and the aurora. In the latter area the release of certain chemical species into the upper atmosphere results in luminous clouds that display the resonance electronic-vibrational-rotational spectrum of the released species. Such spectra are seen in rocket releases of chemicals for upper-atmosphere studies and on reentry into the atmosphere of artificial satellites. Of particular interest in this connection are the observed spectra of certain metallic oxides and air diatomic species. From band-intensity distribution of the spectra and knowledge of the /-values for electronic and vibrational transitions, the local conditions of the atmosphere can be determined.1... 

We pause briefly on the question of the possible mechanism of the effect of admixtures which narrow the limits and flegmatize explosive mixtures. Above we related the limits to thermal properties of the mixture and to the flame velocity. The effect of small amounts of an admixture on the heat conduction, specific heat and thermal radiation cannot be significant. Apparently, as a rule, the role of extinguishing admixtures consists in decreasing the normal flame velocity. Preliminary experiments by Barskii (CO-CCl4, Cl2) and Sadovnikov (H2-SnCl4) confirm this point of view. 

Another approach to radiation loss reduction might be the alteration of the salt water surface in some manner to lower its emissivity for thermal radiation. If a transparent thin liquid film or porous solid film of low thermal emissivity, permeable to water vapor, could be floated on the salt water, solar energy could continue to be absorbed on the basin bottom, water would vaporize, but thermal radiation loss would be reduced. Whether materials with these properties can be found and successfully utilized remains to be seen. 

Applications of thermal radiation spectroscopy to expins and pyrots are readily apparent. As a consequence of the highly exothermic nature of explns and flares, significant thermal radiation is emitted which can serve to characterize the reaction processes. The photometric properties of pyrots have been treated in Vol 8, P505-R. In practice, thermal radiation characteristics of explns do not always closely approximate black body properties since the system is non-equilibrium in nature and is time dependent. In addition, some pyrotechnically related materials such as aluminum oxide and magnesium oxide behave as gray bodies with emissivities well below unity. For such systems the radiant emission is reduced as shown in Fig 4... 

L (70,000 gal). For tanks greater than 266,000 L (70,000 gal), the minimum distance to property lines or buildings shall be 0.7 times the container diameter, but not less than 30 m (100 ft). NFPA 59A also requires that the impoundment area be located to prevent the heat flux from a fire from exceeding certain levels at the property line. The model used to calculate heat flux is described in the Gas Research Institute report GRI0176, LNGFIRE A Thermal Radiation Model for LNG Fires [5.18]. NFPA 59A also recommends that provisions be made to minimize the chance that flammable vapor clouds produced from an LNG spill will reach the property line. The flammable vapor cloud... 

The remote sounding of land covers is based on recording the properties of reflected and scattered electromagnetic radiation. Such a possibility to obtain information about land cover properties is connected here with the facts that the character of proper (thermal) radiation, and the mechanisms of scattering and reflection are closely connected with the physical and geometrical properties of the surface, inadequate knowledge of which can also lead to erroneous conclusions and, hence, is a source of controversy in the information space. 

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