Unsteadiness of the Separation Shock Wave Structure in a Supersonic Compression Ramp Flowfield

Dolling, D. S.; Murphy, M. T.

doi:10.2514/3.60163

Cited by 293 publications

(121 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These studies have shown that when the boundary layer separates, the shock foot and interaction zone undergo an unsteady motion at frequencies much lower than those of the incoming boundary layer. A variety of authors have tried to correlate this unsteady shock wave motion with upstream conditions (Andreopoulos and Muck 1987), as well as the internal dynamics of the separated flow region itself (Dolling and Murphy 1983). Beresh et al (2002), using conditional analysis, showed that the low-frequency motion could be related to the fullness of the instantaneous velocity profile of the incoming boundary layer.…”

Section: Introductionmentioning

confidence: 99%

Particle image velocimetry measurements of a shock wave/turbulent boundary layer interaction

2007

View full text Add to dashboard Cite

Particle image velocimetry is used to investigate the interaction between an incident shock wave and a turbulent boundary layer at Mach 2.1. A particle response assessment establishes the fidelity of the tracer particles.The undisturbed boundary layer is characterized in detail. The mean velocity field of the interaction shows the incident and reflected shock wave pattern, as well as the boundary layer distortion. Significant reversed flow is measured instantaneously, although, on average no reversed flow is observed. The interaction instantaneously exhibits a multi-layered structure, namely, a high-velocity outer region and a low-velocity inner region. Flow turbulence shows the highest intensity in the region beneath the impingement of the incident shock wave. The turbulent fluctuations are found to be highly anisotropic, with the streamwise component dominating. A distinct streamwiseoriented region of relatively large kinematic Reynolds shear stress magnitude appears within the lower half of the redeveloping boundary layer. Boundary layer recovery towards initial equilibrium conditions appears to be a gradual process.

show abstract

Section: Introductionmentioning

confidence: 99%

Particle image velocimetry measurements of a shock wave/turbulent boundary layer interaction

2007

View full text Add to dashboard Cite

show abstract

“…To isolate the shock-motion component of the pressure signal, several studies have employed conditional sampling algorithms [10][11][12][13] . The typical feature is the conversion of the pressure signal into a "boxcar" of amplitude unity and varying frequency.…”

Section: Data Reduction (Two-threshold Method Ttm)mentioning

confidence: 99%

Shock Excursion in Transonic Convex-Corner Flows

Chung

Chang

2016

Int. J. Mod. Phys. Conf. Ser.

View full text Add to dashboard Cite

A typical feature on a transonic airfoil is associated with a quasi-normal shock on the upper surface. When a shock is strong enough, development of a separation bubble changes the flowfield significantly. High intensity of pressure fluctuations is associated with unsteady shock wave. An experimental study was conducted to investigate transonic convex-corner flows, including singleand round-convex corners. Peak pressure fluctuations and zero-crossing frequency are associated with incoming Mach number, total turning angle, and separation length. In the cases of R100 and R200, the level of zero-crossing frequency decreases with increasing turning angle as observed in the single convex-corner flows. An increase in the level of pressure fluctuations corresponds to lower zero-cross frequency. In the cases of R300, there is a roughly constant level of surface pressure fluctuations or the variation of pressure fluctuations with the turning angle is less significant. The zero-crossing frequency would be independent of turning angle in the cases of R300.

show abstract

“…Some candidates include the Mach 3 Smits and Muck database (and the earlier work by Settles and Bogdanoff [31]). The pioneering study of Dolling and Murphy [34] also corresponds to these compressioncorner experiments, so there is data available on shock-system dynamics.…”

Section: Directions For Future Workmentioning

confidence: 99%

Simulation of Transient Dynamics of Shock Wave Boundary Layer Interactions Using Hybrid Large-Eddy/Reynolds-Averaged Navier-Stokes Models

Edwards¹

2007

View full text Add to dashboard Cite

Public Reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comment regarding this burden estimates or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and 49624.1-EG-IISimulations of the Mach 5 compression-corner shock / turbulent boundary layer interaction experimentally mapped by Prof. David Dolling and co-workers have been performed using a hybrid large-eddy / Reynolds-averaged Navier-Stokes (LES/RANS) model. The model captures the mean-flow structure of the interaction reasonably well, with observed deficiencies traced to an underprediction of the displacement effects of the shock-induced separation region. The computational results provide some support for a recent theory relating to the underlying causes of low-frequency shock wave oscillation. The simulation results indicate that the sustained presence of a collection of neighboring streaks of low / high momentum fluid within the boundary layer induces a lowfrequency undulation of the separation front. Power spectra obtained at various streamwise stations are in good agreement with experimental results, indicating that the LES/RANS method is capable of predicting both the low and high-frequency dynamics of the interaction. Downstream of re-attachment, the simulations capture a three-dimensional mean flow structure, dominated by counter-rotating vortices that produce wide variations in the surface skin friction. Predictions of the structure of the re-attaching boundary layer agree well with experimental pitot pressure measurements. In comparison with Reynolds-averaged model predictions, the LES/RANS model predicts more amplification of Reynolds stresses and a broadening of the Reynolds-stress distribution within the boundary layer that is probably due to re-attachment shock motion.40 hybrid large-eddy / Reynolds-averaged Navier-Stokes simulations, shock wave / turbulent boundary layer interaction, shock system dynamics Project Abstract (Original Proposal)Many experimental investigations have noted that complex shock / boundary layer interactions exhibit large-scale, low frequency motion that is distinct from that associated from wall-layer turbulence. This motion results in fluctuating pressure and heat-transfer loads that can adversely affect the performance of supersonic missile systems, among others. Accurate predictions of such effects would appear to require a time-dependent modeling strategy, such as large-eddy simulation (LES) or direct numerical simulation (DNS). The application of these techniques to flows at practical Reynolds numbers requires immense computational resources, and as yet, very few studies have...

show abstract

Unsteadiness of the Separation Shock Wave Structure in a Supersonic Compression Ramp Flowfield

Cited by 293 publications

References 12 publications

Particle image velocimetry measurements of a shock wave/turbulent boundary layer interaction

Particle image velocimetry measurements of a shock wave/turbulent boundary layer interaction

Shock Excursion in Transonic Convex-Corner Flows

Simulation of Transient Dynamics of Shock Wave Boundary Layer Interactions Using Hybrid Large-Eddy/Reynolds-Averaged Navier-Stokes Models

Contact Info

Product

Resources

About