Introduction

The study of heat transfer has, in the recent past, become a matter of considerable importance and interest because of the growing demand for energy, environmental comfort, safety, rapid transportation, and advanced materials, and the need to optimize processes that involve energy transport. Heat transfer is concerned with the physical processes underlying the transport of thermal energy due to a temperature difference or gradient. Interest lies in determining the rate of heat transfer, the temperature eld that results, and the associated uid o w that arises in many of these processes. There are two basic processes by which heat transfer occurs: conduction and radiation. Conduction occurs if a temperature gradient exists in a material and is due to the thermal motion of the microscopic particles that constitute the material. This chapter also presents an overview of the key concepts discussed in this book.