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A critical examination of the validity of simplified models for radiant heat transfer analysis.Examination of the directional effects of the simplified models by comparing the experimental data with the predictions based on simple and more detailed models for the radiation characteristics of surfaces. Analytical results indicate that the constant property diffuse and specular models do not yield the upper and lower bounds on local radiant heat flux. In general, the constant property specular analysis yields higher values of irradiation than the constant property diffuse analysis. A diffuse surface in the enclosure appears to destroy the effect of specularity of the other surfaces. Semigray and gray analyses predict the irradiation reasonably well provided that the directional properties and the specularity of the surfaces are taken into account. The uniform and nonuniform radiosity diffuse models are in satisfactory agreement with each other.
Document ID
19720054733
Document Type
Reprint (Version printed in journal)
Authors
Toor, J. S.
Viskanta, R. (Purdue University Lafayette, Ind., United States)
Date Acquired
August 6, 2013
Publication Date
August 1, 1972
Publication Information
Publication: International Journal of Heat and Mass Transfer
Volume: 15
Subject Category
THERMODYNAMICS AND COMBUSTION
Funding Number(s)
CONTRACT_GRANT: NAS9-8118
Distribution Limits
Public
Copyright
Other