ABSTRACT
This chapter presents the inverse radiation problems for an absorbing, emitting, isotropically scattering plane-parallel medium and for a medium with spherical symmetry. It examines the inverse problem of estimating the unknown temperature field in an absorbing, emitting, isotropically scattering semi-transparent solid sphere, by utilizing the measured exit radiation intensities. In the study of radiation heat transfer, a distinction is made between radiation transfer as a surface phenomenon and as a bulk phenomenon. A semi-transparent medium may scatter radiation in addition to absorbing and emitting it. That is, when a beam of radiation strikes a semi-transparent body, some of the incident beam is reflected from the surface, the remaining portion penetrates into the medium, where part of the radiation energy is absorbed by the body, and the remaining portion passes out through the medium, if the medium is not a strong absorber.
