ABSTRACT
This chapter presents the fundamentals of radiation heat transfer and advanced methods of analysis. It includes the electromagnetic spectrum, governing equations, radiation exchange between surfaces, radiation in enclosures, and solar energy. The chapter examines radiation exchange between diffuse gray surfaces in an enclosure. Two fundamental theories are core to the physics of radiation and electromagnetic waves: quantum theory and electromagnetic theory. A blackbody is an ideal surface that absorbs all incident radiation, irrespective of wavelength and direction. The spectral distribution of solar radiation can be approximated by blackbody radiation at 5,800 K with a maximum emissive power in the visible region of the spectrum. The performance of solar collectors is often expressed in terms of a collector efficiency factor and a collector heat removal factor. In dual-wavelength radiation thermometry, measurements of the radiance at two different wavelengths and the surface emissivity are used in a compensation algorithm to determine the surface temperature.
