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Thermophysics and Aeromechanics

, Volume 25, Issue 5, pp 667–673 | Cite as

Stability of time-periodic flow with laminar boundary-layer separation

  • A. V. Boiko
  • A. V. Dovgal
  • A. M. Sorokin
Article
  • 9 Downloads

Abstract

The influence of the low-frequency modulation of flow behind a rectangular backward-facing step on the amplitude characteristics of disturbances in the separated laminar boundary layer has been studied. The experimental data were obtained by the method of hot-wire anemometry in a wind tunnel at a low subsonic velocity. Response of the separated flow to the long-wave oscillations generated by a local source of disturbances on the surface of the experimental model was clarified. The low-frequency nonstationarity of the separation region leads to a growth of velocity fluctuations in the separated boundary layer, which dominate the laminar-turbulent transition and the state of the flow in the near-wall region.

Key words

hydrodynamic stability boundary-layer separation flow past a backward-facing step unsteady flow 

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Copyright information

© Kutateladze Institute of Thermophysics, Siberian Branch of the Russian Academy of Sciences 2018

Authors and Affiliations

  1. 1.Khristianovich Institute of Theoretical and Applied Mechanics SB RASNovosibirskRussia
  2. 2.Tyumen State UniversityTyumenRussia

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