Measurement of turbulence characteristics in compressible boundary layers near separation zones

Zheltovodov, A. A.; Lebiga, V. A.; Yakovlev, V. N.

doi:10.1007/bf00850765

Cited by 3 publications

(5 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, due to the compressibility effects, the turbulence amplification was believed to be caused by more than the adverse pressure gradient. Smits & Muck (1987) postulated that multiple plausible flow features might be responsible, such as the low-frequency shock motions, the direct shock wave/turbulence interaction (Zheltovodov et al 1989), the generation of acoustic and entropy waves (Anyiwo & Bushnell 1982), the shear layer induced by the flow separation (Rose & Childs 1974;Selig et al 1989), and the curvation of the streamlines (Andreopoulos et al 2000). The direct numerical simulations (DNS) by Wu & Martin (2007 confirmed that the turbulence amplification can be attributed to the nonlinear coupling of vorticity, entropy, and the 'pumping' of turbulent fluctuations from the mean flow.…”

Section: Turbulence Amplification and Coherent Structuresmentioning

confidence: 99%

“…Early experimental studies (e.g. Smits & Muck 1987; Zheltovodov, Lebiga & Yakovlev 1989) showed that in supersonic flows over compression corners, where an oblique shock emerges due to the mean flow compression, the Reynolds stress is amplified. As the turning angle of the corner increases, the stronger compression leads to the increment of the pressure gradient, further resulting in higher amplification rates.…”

Section: Introductionmentioning

confidence: 99%

“…Smits & Muck (1987) postulated that multiple plausible flow features might be responsible, such as the low-frequency shock motions, the direct shock wave/turbulence interaction (Zheltovodov et al. 1989), the generation of acoustic and entropy waves (Anyiwo & Bushnell 1982), the shear layer induced by the flow separation (Rose & Childs 1974; Selig et al. 1989), and the curvation of the streamlines (Andreopoulos et al.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

A spectral inspection for turbulence amplification in oblique shock wave/turbulent boundary layer interaction

Zhao

Tang

et al. 2022

J. Fluid Mech.

View full text Add to dashboard Cite

Turbulence amplification and the large-scale coherent structures in shock wave/turbulent boundary layer interaction flows have been studied at length in previous research, while the direct association between these two flow features is still lacking. In the present study, the transport equation of turbulent kinetic energy spectra is derived and utilized to analyse the scale-by-scale energy budget across the interaction zone, enabling us to reveal the association between the genesis of the large-scale motions and the turbulence amplification. For the presently considered flow with incipient shock-induced separation, we identified in turbulent kinetic energy spectra distribution that the most energetic motions are converted from the near-wall small-scale motions to large-scale motions consisting of velocity streaks and cross-stream circulations as they go through the interaction zone. The amplification of streamwise velocity fluctuation is triggered first, resulting in the emergence of large-scale velocity streaks, which is attributed to the adverse pressure gradient, as indicated by the spectra of the production term. The energy carried by large-scale velocity streaks is transferred to other velocity components by the pressure-strain term, producing large-scale cross-stream circulations. When large-scale motions are convected downstream, their energy is transferred via turbulent cascade to smaller scales and dissipated by viscosity. The spanwise uniform fluctuations, reminiscent of the unsteadiness of the separation bubble, are contributed primarily by the inter-scale energy transfer from the finite spanwise scale motions.

show abstract

Section: Turbulence Amplification and Coherent Structuresmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A spectral inspection for turbulence amplification in oblique shock wave/turbulent boundary layer interaction

Zhao

Tang

et al. 2022

J. Fluid Mech.

View full text Add to dashboard Cite

show abstract

“…These mechanisms are essentially nonlinear and cannot be captured or predicted by LIA. The experimental research of compression corners at Mach 2.9 of Zheltovodov & Yakovlev (1986) and Zheltovodov, Lebiga & Yakovlev (1989) also demonstrated turbulence amplification in the separated boundary layer across the shock wave. By using the method of diagrams of Kovaszhnay (1953), they revealed the acoustic mode of the disturbances in the external flow above the separated shear layers.…”

mentioning

confidence: 90%

On the turbulence amplification in shock-wave/turbulent boundary layer interaction

et al. 2020

View full text Add to dashboard Cite

“…These velocity and pressure fluctuations travel upstream, leading to low-frequency unsteady shock motions and the 'breathing' of separation bubbles (Ganapathisubramani, Clemens & Dolling 2007;Wu & Martin 2008;Priebe & Martín 2012;Clemens & Narayanaswamy 2014). They are also convected downstream by the mean flow, resulting in the intensification of wall heat flux and pressure fluctuations (Bernardini, Pirozzoli & Grasso 2011;Volpiani, Bernardini & Larsson 2018, 2020, the enhancement of mass and momentum entrainment between the boundary layer and free-stream flow (Wu & Martin 2007Piponniau et al 2009;Priebe & Martín 2012) and the amplification of the Reynolds stress (Smits & Muck 1987;Zheltovodov, Lebiga & Yakovlev 1989;Fang et al 2020;Yu et al 2022).…”

Section: Introductionmentioning

confidence: 99%

Post-shock turbulence recovery in oblique-shock/turbulent boundary layer interaction flows

Dong

Liu

et al. 2023

J. Fluid Mech.

View full text Add to dashboard Cite

The oblique shock impinging on the supersonic turbulent boundary layer leads to a mixing layer and the emergence of large-scale coherent structures within the interaction zone which leave significant velocity defect and turbulence amplification downstream. In the present study, we investigate the turbulence recovery in the post-shock region by exploiting direct numerical simulation data of the oblique-shock/turbulent boundary layer interaction flow at the incoming Mach number of $2.28$ and the shock angle of $33.2^\circ$ , with special attention paid to the contribution of the mixing layer and large-scale structures to flow dynamics. For that purpose, we propose to split the mean velocity, Reynolds stresses and spanwise spectra into a canonical portion that is constructed according to the statistics of canonical turbulent boundary layers, and a mixing-layer-induced portion. We found that the hidden mixing layer grows with the boundary layer thickness and that the induced mean shear and Reynolds stresses decay at different rates. The mean velocity recovers to the canonical profiles at a distance of 13 boundary layer thicknesses downstream where the mixing-layer-induced mean shear ceases to have strong impacts. The recovery of Reynolds stresses requires 10 boundary layer thicknesses in the near-wall region but a much longer streamwise extent in the outer region due to the slow decay of large-scale motions. These large-scale motions superpose on the near-wall turbulence, intensifying the turbulent fluctuations, yet having a trivial impact on the skin friction, for the contribution of the mixing-layer-induced mean shear and Reynolds shear stress are balanced by the advection term. We further establish a simple physical model capable of approximately predicting the streamwise evolution of mixing-layer-induced mean shear and turbulent kinetic energy. This model suggests that the complete recovery of turbulence in the outer region requires a streamwise extent of approximately 50 boundary layer thicknesses.

show abstract

Measurement of turbulence characteristics in compressible boundary layers near separation zones

Cited by 3 publications

References 6 publications

A spectral inspection for turbulence amplification in oblique shock wave/turbulent boundary layer interaction

A spectral inspection for turbulence amplification in oblique shock wave/turbulent boundary layer interaction

On the turbulence amplification in shock-wave/turbulent boundary layer interaction

Post-shock turbulence recovery in oblique-shock/turbulent boundary layer interaction flows

Contact Info

Product

Resources

About