This paper analyzes transient radiation and conduction heat transfer through planar porous materials. The transient response considered is caused by a sudden increase of heat generation at the hot boundary. The objective was to establish the effect of radiation on the temperature rise of the hot wall. The problem investigated is relevant to the use of transient methods for measuring the thermal conductivity of porous insulations. It was found that, in cases such as when the porous material is a light-weight fiberglass insulation, neglecting radiation would result in serious errors in predicting the hot wall temperature rise.
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Lii, C.C. and Ozisik, M.N., "Transient Radiation and Conduction in an Absorbing, Emitting, Scattering Slab with Reflective Boundaries," International Journal of Heat and Mass Transfer, Vol. 15, pp. 1175-1179 (1972 ).
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Weston, K.C. and Hauth, J.L., "Unsteady, Combined Radiation and Conduction in an Absorbing, Scattering, and Emitting Medium" Journal of Heat Transfer, Vol.95, pp. 357-364 (1973).
11.
Tong, T.W., Birkebak, R.C., and Enoch, I.E., "Thermal Radiation, Convection and Conduction in Porous Media Contained in Vertical Enclosures," Journal of Heat Transfer, Vol. 105, pp. 414-418 (1983) (also see the conference paper version for more details on the method of solution, ASME Paper No. 82-HT-50).
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13.
Tong, T.W., Yang, Q.S., and Tien, C.L., "Radiative Heat Transfer in Fibrous Insulations—Part II: Experimental Study," Journal of Heat Transfer, Vol. 105, pp. 76-81 (1983).
14.
Graves, R.S. , Yarbrough, D.W., and McElroy, D.L., "Apparent Thermal Conductivity Measurements by an Unguarded Technique ," Thermal Conductivity 18, Ashworth, T. and Smith, D. R. (Editors), Plenum Publishing Corporation , pp. 339-355 (1985).
