ABSTRACT
This chapter provides an introduction to radiation heat transfer. Radiation heat transfer is entirely different from heat transfer by conduction or convection. Radiation is an electromagnetic mechanism by which energy is transported at the speed of light through regions that are devoid of substance. The principles of quantum mechanics provide a quantitative description of how radiation is produced by a solid body. The radiation spectrum encompasses many forms: radio waves, microwaves, infrared waves, ultraviolet waves, x-rays, and gamma rays. The chapter presents the radiation laws: Kirchhoff’s law, Planck’s distribution law, and Wien’s displacement law. It examines characteristics of a few real surfaces and saw that real surfaces do depart significantly from ideal-surface behavior. The normal emissivity is that measured by a device located normal to the surface of interest.
