After the RM instability grows from a first shock, it can be hit by a second shock. These reshock scenarios have been found in the key applications of inertial confinement fusion implosions or supernova explosions. In this chapter, I will introduce the efforts to model the growth of the mixing layer induced by the first shock and subsequent reshock and describe how the turbulence kinetic energy and anisotropy might be affected by the reshock events. Data from shock tube experiments and numeric simulations will also be introduced to provide insight into the reshock RM induced flows.

Chapter 6 deals with 2-D laminar boundary-layer instabilities and their control. It covers the full range of Mach numbers from incompressible to hypersonic. Boundary-layer instabilities leading to turbulence onset is of great practical importance. This chapter reviews methods of analysis of boundary-layer stability and illustrates several linear and nonlinear mechanisms that can play a role in the breakdown to turbulence. Such understanding is intrinsic to the methods of boundary-layer instability control that are presented in the chapter. Both passive and active flow control approaches are presented.

Chapter 7 deals with 3-D laminar boundary-layer instabilities and their control. It covers the full range of Mach numbers from incompressible to hypersonic. A practical example of a 3-D boundary layer is the flow over a swept wing, which is susceptible to four types of instabilities that can lead to turbulence onset. Of these, cross-flow instability is the most dominant and therefore the most studied 3-D boundary-layer instability mechanism. A fundamental understanding of the instability has led to methods of control that have been successfully demonstrated at incompressible to hypersonic Mach numbers. These and other methods of control are presented.