Journal of Visualization

, Volume 18, Issue 4, pp 619–629 | Cite as

Visualization of supersonic flow around a sharp-edged, sub-boundary-layer protuberance

  • Frank K. LuEmail author
Regular Paper


Innovations in conventional surface and planar laser scattering visualizations revealed complex structures in the Mach 2.5 flow past a sharp-edged, sub-boundary-layer ramp with swept sides that is one type of micro vortex generator (MVG). The incoming flow separated over the leading edge despite the ramp angle being below the threshold for incipient separation. The separation produced a weak trailing horseshoe vortex system. The flow over the top of the MVG separated off the slant edges to produce a large primary vortex pair. Extra details were revealed at the trailing edge with at least two pairs of singularities. Vortex filaments spring from these singularities. Symmetry breaking from the confluence of the two primary vortices was observed as an unsteady wake to result in a train of possibly ring or hairpin vortices trailing downstream.

Graphical Abstract


Protuberance Flow topology Viscous–inviscid interaction Flow visualization 



The author thanks Adam Pierce and Yusi Shih for their assistance with the experiments, and Prof. Chaoqun Liu and Dr. Qin Li for their insightful comments. Support of the research by an AFOSR Grant No. FA9550-08-1-0201 monitored by Dr. John Schmisseur is gratefully acknowledged.

Supplementary material

Supplementary material 1 (wmv 5474 KB)

Supplementary material 2 (wmv 8325 KB)

Supplementary material 3 (wmv 8568 KB)

Supplementary material 4 (wmv 18403 KB)


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Copyright information

© The Visualization Society of Japan 2015

Authors and Affiliations

  1. 1.Mechanical and Aerospace Engineering Department, Aerodynamics Research CenterUniversity of Texas at ArlingtonArlingtonUSA

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