Physics of Microwave Heating

Microwave heating generates heat by absorption and loss of energy. Accordingly, how does a substance turn microwave into heat? How does one measure the efficiency of microwave heating? These topics require to be understood. As such, this chapter provides some commentaries on these topics. Furthermore, a method for measuring the heating efficiency of microwaves, impedance matching is also explained. There are books out there that presume that microwave heating refers to heating in which dielectric heating proceeds. This is not entirely correct, as there are several types of microwave heating phenomena. This chapter also describes the type of microwave heating through illustrations and some equations. Furthermore, actual examples and chemical reactions are given; such topics as the penetration depth of microwaves, the skin effect, the frequency effect, simulation of electromagnetic waves, and electrothermal and transmission modes are discussed. The coffee break shows the proper usage of microwave ovens.