Stability of time-periodic flow with laminar boundary-layer separation
A.V. Boiko1, 2, A.V. Dovgal1, and A.M. Sorokin1
1Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia
2Tyumen State University, Tyumen, Russia
E-mail: boiko@itam.nsc.ru, dovgal@itam.nsc.ru
Keywords: hydrodynamic stability, boundary-layer separation, flow past a backward-facing step, unsteady flow
Pages: 667–673
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.
DOI: 10.1134/S0869864318050037
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