chapter  4
58 Pages

Theory of Characteristics

The concept of characteristics as trajectories of small disturbances in supersonic and unsteady subsonic flowswas presented in Chapter 2 (and even earlier, in Section 1.6, where they were treated as Mach lines). In what follows, the theory of characteristics (as a part of the theory of mathematical physics equations) is outlined as applied to gas dynamic equations.Most of the chapter is devoted to gas dynamic applications of the theory to an analysis of general and local flow properties. It involves solutions for compression and expansion waves, shock wave initiation, and interaction of disturbances with flow inhomogeneities, such as, for example, shock waves.