Time-resolved volumetric particle tracking velocimetry of large-scale vortex structures from the reattachment region of a laminar separation bubble to the wake

Abstract

The present paper presents time-resolved volumetric Particle Tracking Velocimetry measurements in a water towing tank on a SD7003 airfoil, performed at a Reynolds number of 60,000 and a 4° angle of attack. The SD7003 airfoil was chosen because of its long mid-chord and stable laminar separation bubble (LSB), occurring on the suction side of the airfoil at low Reynolds numbers. The present study focuses on the temporal resolution of unsteady large-scale vortex structures emitted from the LSB. In contrast to other studies, where only the observation of the flow in the transition region was examined, the entire flow from the leading edge to the far wake of the airfoil was investigated here.

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Acknowledgments

The authors like to thank Prof. Münch and Mr. Banachowicz from the University of German Armed Forces Munich for providing the test facility and their technical support.

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Correspondence to E. Wolf.

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Wolf, E., Kähler, C.J., Troolin, D.R. et al. Time-resolved volumetric particle tracking velocimetry of large-scale vortex structures from the reattachment region of a laminar separation bubble to the wake. Exp Fluids 50, 977–988 (2011). https://doi.org/10.1007/s00348-010-0973-2

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Keywords

  • Vortex
  • Particle Image Velocimetry
  • Vortex Structure
  • Suction Side
  • Adverse Pressure Gradient