1.3: Energy Conservation Processes

A theme of the chapters to follow is conversion of energy between electrical and mechanical forms The relation between electromechanical power flow and the product of electric or magnetic stress and material velocity is first emphasized in Chapter 4. Rotating machines deserve to be highlighted in this basic sense, because for bulk power generation they are a standard for comparison. But, even where kinematic systems are superseded by those involving self-consistent interactions, there is value in considering the kinematic examples. They make clear the basic objectives governing the engineering of materials and fields even when the objectives are achieved by more devious methods. For example, the synchronous interactions with constrained charged particles are not directly applicable to practical devices, but highlight the basically electroquasistatic electric shear stress interaction that underlies electron beam interactions in Chapter 11.

The classification of energy conversion processes made in Chapter 4 provides a frame of reference for many of the self-consistent interactions described in later chapters. Thus, d-c rotating machines from Chapter 4 have counterparts with fluid conductors in Chapter 9, and the Van de Graaff generator is a prototype for the gasdynamic models developed in Chaps. 5 and 9. Electric and magnetic induction machines, respectively taken up in Chaps. 5 and 6, are a prototype for induction interactions with fluids in Chapter 9, And, the synchronous interactions of Chapter 4 motivate the self-consistent electron beam interactions of Chapter 11.