Published online by Cambridge University Press: 22 November 2018
Chapter 4 addresses the important topic of spatial instability for spatially evolving flows, such as shear layers, jets and wakes. The chapter starts out with a derivation of Gaster’s transformation that allows spatial growth rates to be computed from temporal growth rates. The chapter also presents a dicussion of absolute and convective instabilites, and of wavepackets. It concludes with a discussion of dicrete and continuous spectra.