Shock wave-boundary layer interaction in a transitional flow over a backward-facing step

Shock wave-boundary layer interaction in a transitional flow over a backward-facing step

Hu, W. (TU Delft Aerodynamics)
Hickel, S. (TU Delft Aerodynamics)
van Oudheusden, B.W. (TU Delft Aerodynamics)

2019

The unsteadiness of shock wave-boundary layer interactions is investigated in a transitional backward-facing step flow at Ma=1:7 and Red0 =13718 using large eddy simulation. The mean and instantaneous flow shows that the laminar inflow undergoes a laminar-to-turbulence transition in which Kelvin-Helmholtz vortices form, distort and eventually break down into small hairpin-like vortices. The interaction system features broadband frequency oscillations in a range f d0=u¥ = 0:03 _ 0:23 based on the spectral and statistical analysis. The results of dynamic mode decomposition indicate that the medium-frequency motions centered at f d0=u¥ = 0:06 are related to the shock winkling and the shedding of large coherent vortices, while the lower (centered at f d0=u¥ _ 0:01) and higher ( f d0=u¥ _ 0:1) frequency unsteadiness is associated with the periodical dilatation and shrinking of separation system and the convection of upstream K-H vortices respectively.

http://resolver.tudelft.nl/uuid:456a43de-3793-48f8-bf9f-4ee19fb93764

54th 3AF International Conference AERO2019 At: Paris, France

54th 3AF International Conference on Applied Aerodynamics, 2019-03-25 → 2019-03-27, Paris, France

Institutional Repository

conference paper

© 2019 W. Hu, S. Hickel, B.W. van Oudheusden