Three-dimensional structure of the compressible mixing layer of an axisymmetric, supersonic, separated flow

Branden M. Kirchner, Tyler J. Tetef, Gregory S. Elliott, J. Craig Dutton

Research output: Chapter in Book/Report/Conference proceedingConference contribution


The coherence of three-dimensional turbulence in the compressible mixing layer of an axisymmetric, Mach 2.49, separated flow field is investigated experimentally by means of non-time-correlated tomographic particle image velocimetry (tomo-PIV) measurements. Validation of the tomo-PIV data is performed by comparison with reliable data of the same flow field acquired using stereoscopic PIV and laser Doppler velocimetry. Statistical evidence of both hairpin vortex structures as well as counter-hairpins within the mixing layer was found by conditionally averaging the flow field measurements utilizing linear stochastic estimation. The dependence of the streamwise and transverse spatial location within the mixing layer, as well as the effect of flow field recompression on these structures is presented. The size, coherence, and angular orientation of the conventional-hairpins are shown to be strongly dependent on both the streamwise coordinate, as well as the onset of the adverse pressure gradient induced by recompression. For the counter-hairpins, however, only a mild dependence of the streamwise coordinate or the onset of recompression was found until the flow field approached the point at which low momentum fluid is turned to be recirculated upstream. These structures were found to commonly exist throughout the mixing layer and occur statistically in conjunction with one another throughout a significant transverse extent of the mixing layer. Distinct regions within the mixing layer that are statistically dominated by either conventional or counter-hairpins are identified and their implications discussed. Additionally, the dynamics of the counter-hairpin structures suggest a mechanism of potentially effective flow control which, if feasible, could have a profound impact on the net vehicle drag of a blunt-faced cylindrical body in supersonic flight.

Original languageEnglish (US)
Title of host publication2018 Fluid Dynamics Conference
PublisherAmerican Institute of Aeronautics and Astronautics Inc, AIAA
ISBN (Print)9781624105531
StatePublished - 2018
Event48th AIAA Fluid Dynamics Conference, 2018 - Atlanta, United States
Duration: Jun 25 2018Jun 29 2018

Publication series

Name2018 Fluid Dynamics Conference


Other48th AIAA Fluid Dynamics Conference, 2018
Country/TerritoryUnited States

ASJC Scopus subject areas

  • Aerospace Engineering
  • Engineering (miscellaneous)


Dive into the research topics of 'Three-dimensional structure of the compressible mixing layer of an axisymmetric, supersonic, separated flow'. Together they form a unique fingerprint.

Cite this