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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Arakeri, J.H., Das, S., Srinivasan, U. (2006). LOCALISED INSTABILITY IN UNSTEADY SEPARATION BUBBLES. In: Govindarajan, R. (eds) IUTAM Symposium on Laminar-Turbulent Transition. Fluid Mechanics and Its Applications, vol 78. Springer, Dordrecht. https://doi.org/10.1007/1-4020-4159-4_6
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DOI: https://doi.org/10.1007/1-4020-4159-4_6
Publisher Name: Springer, Dordrecht
Print ISBN: 978-1-4020-3459-6
Online ISBN: 978-1-4020-4159-4
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