Abstract
When a “normal” shock wave is introduced into a duct by controlling the upstream or back pressure, it interacts with the boundary layer which develops along the duct. In the case that the interaction is significant, the shock no longer remains a single normal shock, but gives way to a complex pattern of multiple shocks closely following one another. Such a multi-shock system is called a pseudo-shock wave.
A review is given on the pseudo-shock waves. Some characteristics such as the pressure recovery, the length, and the oscillation of a pseudo-shock are discussed, and the flow models presented so far are explained. Pseuso-shocks may appear anywhere in ducts and passages where normal shocks are supposed to stand and interact with wall boundary layers. Some of these examples are also described.
