ABSTRACT
This chapter deals with engineering calculation of radiation exchange between surfaces separated by a nonparticipating medium. It reviews the physics of radiation and defines the gray surface model and also deals with methods for calculating radiation heat exchange between surfaces, first for black surfaces and then for diffuses gray surfaces. The chapter explores the diffuse gray surface model to problems involving solar and atmospheric radiation by allowing for a different value of absorptance to short-wavelength solar radiation. It examines directional characteristics of surface radiation. The chapter discusses Spectral characteristics of surface radiation, with the limited objective of demonstrating how to calculate total hemispherical radiation properties from experimental data for spectral values. It describes radiation transfer through gases. Data for total radiation properties are given, and analytical methods are developed for some simple radiation exchange problems in enclosures containing combustion gases. Radiation exchange between black surfaces is rather easy to analyze because all the radiation falling on a surface is absorbed.
