Transition control

A unified view of the different control methods available or contemplated to delay or advance transition is presented. Emphasis is placed on two-dimensional incompressible flows, although more complex situations are also briefly covered. The governing equations are developed first, the routes to transition are mapped, and elements of the linear stability theory are outlined. The four basic stability modifiers - wall motion, suction, shaping, and wall heat transfer - are discussed, along with wave cancellation. The benefits as well as drawbacks of each approach are considered.