2007 Volume 2 Issue 3 Pages 535-546
The current understanding of supersonic boundary layer transition is reviewed in this paper. The material focuses on bypass transition in a plane supersonic boundary layer. Recent advances in DNS and engineering prediction of transition are discussed. It is shown that streaky structures appear in supersonic boundary layers and that the fluctuation energy growth is proportional to the downstream distance. Spatial DNS studies indicate a bypass transition scenario, breakdown mechanisms to turbulence, and turbulent boundary layer structures.