LOCALISED INSTABILITY IN UNSTEADY SEPARATION BUBBLES

  • Jaywant H. Arakeri
  • S.P. Das
  • Usha Srinivasan
Conference paper
Part of the Fluid Mechanics and Its Applications book series (FMIA, volume 78)

Abstract

We propose an experimental method to study the instability of thin unsteady separation bubbles, i.e. of unsteady boundary layers with reverse flow. The unsteady boundary layer is created by controlled temporal and spatial variations of the velocity external to the boundary layer. We present results of the evolution of instability in different temporally varying flows in a shallow angle diffuser. Depending on the extent of reverse flow in the boundary we observe that instability can be spatially localised.

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Copyright information

© Springer 2006

Authors and Affiliations

  • Jaywant H. Arakeri
    • 1
  • S.P. Das
    • 1
  • Usha Srinivasan
    • 1
  1. 1.Department of Mechanical EngineeringIndian Institute of ScienceBangaloreIndia

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