ABSTRACT
This chapter introduces the modes of heat transfer: convection, conduction and radiation. It discusses radiation between two parallel surfaces. The chapter defines the overall heat transfer coefficient for combined modes of heat transfer. It evaluates the overall heat transfer coefficient using a thermal resistance analogy. Heat is a form of energy that is transferred across the boundary of a thermofluid system as a result of a temperature difference. The greater the temperature difference the more rapidly will the heat be transferred. There are three distinct modes of heat transfer convection, conduction and radiation. Conduction can occur within both solids and fluids. Since thermal conductivity is analogous to electrical conductivity, it would follow that metals, having good electrical conductivity, should have good thermal conductivity. Radiation is a form of electromagnetic energy transmission and takes place between all matter providing that it is at a temperature above absolute zero.
