Supersonic vortex breakdown during vortex/cylinder interaction

I. M. Kalkhoran, M. K. Smart, F. Y. Wang

Research output: Contribution to journalArticle

Abstract

The head-one interaction of a supersonic streamwise vortex with a circular cylinder reveals a vortex breakdown similar in many ways to that of incompressible vortex breakdown. In particular, the dramatic flow reorganization observed during the interaction resembles the conical vortex breakdown reported by Sarpkaya (1995) at high Reynolds number. In the present study, vortex breakdown is brought about when moderate and strong streamwise vortices encounter the bow shock in front of a circular cylinder at Mach 2.49. The main features of the vortex/cylinder interaction are the formation of a blunt-nosed conical shock with apex far upstream of the undisturbed shock stand-off distance, and a vortex core which responds to passage through the apex of the conical shock by expanding into a turbulent conical flow structure. The geometry of the expanding vortex core as well as the location of the conical shock apex are seen to be strong functions of the incoming vortex strength and the cylinder diameter. A salient feature of the supersonic vortex breakdown is the formation of an entropy-shear layer, which separates an interior subsonic zone containing the burst vortex from the surrounding supersonic flow. In keeping with the well-established characteristics of the low-speed vortex breakdown, a region of reversed flow is observed inside the turbulent subsonic zone. The steady vortex/cylinder interaction flow fields generated in the current study exhibit many characteristics of the unsteady vortex distortion patterns previously observed during normal shock wave/vortex interactions. This similarity of the instantaneous flow structure indicates that the phenomenon previously called vortex distortion by Kalkhoran et al. (1996) is a form of supersonic vortex breakdown.

Original languageEnglish (US)
Pages (from-to)351-380
Number of pages30
JournalJournal of Fluid Mechanics
Volume369
StatePublished - Aug 25 1998

Fingerprint

vortex breakdown
Vortex flow
vortices
interactions
shock
apexes
circular cylinders
conical flow
normal shock waves
reversed flow
Flow structure
Circular cylinders
supersonic flow
high Reynolds number
shear layers
bows
encounters
upstream
low speed
bursts

ASJC Scopus subject areas

  • Computational Mechanics
  • Mechanics of Materials
  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

Kalkhoran, I. M., Smart, M. K., & Wang, F. Y. (1998). Supersonic vortex breakdown during vortex/cylinder interaction. Journal of Fluid Mechanics, 369, 351-380.

Supersonic vortex breakdown during vortex/cylinder interaction. / Kalkhoran, I. M.; Smart, M. K.; Wang, F. Y.

In: Journal of Fluid Mechanics, Vol. 369, 25.08.1998, p. 351-380.

Research output: Contribution to journalArticle

Kalkhoran, IM, Smart, MK & Wang, FY 1998, 'Supersonic vortex breakdown during vortex/cylinder interaction', Journal of Fluid Mechanics, vol. 369, pp. 351-380.
Kalkhoran IM, Smart MK, Wang FY. Supersonic vortex breakdown during vortex/cylinder interaction. Journal of Fluid Mechanics. 1998 Aug 25;369:351-380.
Kalkhoran, I. M. ; Smart, M. K. ; Wang, F. Y. / Supersonic vortex breakdown during vortex/cylinder interaction. In: Journal of Fluid Mechanics. 1998 ; Vol. 369. pp. 351-380.
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