### NASA Technical Reports Server (NTRS)

Fluctuations and massive separation in three-dimensional shock-wave/boundary-layer interactions Shock-wave unsteadiness was observed in rapidly compressed supersonic turbulent boundary layer flows with significant separation. A Mach 2.85 shock-wave/turbulent boundary layer flow was set up over a series of cylinder-flare bodies in the High Reynolds Number Channel 1.

Get Price### Characterization of Unsteadiness in an Overexpanded

an internal recompression shock forms and boundary-layer separation occurs. The consequent shock-wave turbulent boundary-layer interaction (SWBLI) causes the shedding of vortical structures and the unsteadiness in the shock-wave position. In such a situation dynamicsideloadsareproduced whichcanevenleadtothefailureof

Get Price### Turbulence Structure and Large-Scale Unsteadiness in

Turbulence Structure and Large-Scale Unsteadiness in Shock-Wave / Boundary Layer Interaction Kevin M. Porter and Jonathan Poggiey Purdue University West Lafayette IN 47906 The effects of unsteady separation on the structure of a turbulent boundary layer were explored using wall-resolved implicit large eddy simulation.

Get Price### Control of unsteadiness of a shock wave/turbulent

Control of unsteadiness of a shock wave/turbulent boundary layer interaction by using a pulsed-plasma-jet actuator Venkateswaran Narayanaswamy Laxminarayan L. Raja and Noel T. Clemensa) Department of Aerospace Engineering and Engineering Mechanics The University of Texas at Austin Austin Texas 78712 USA

Get Price### Low-Frequency Unsteadiness in DNS of Shock

The interaction of a shock wave with a turbulent boundary layer (STBLI) is ubiquitous in compressible ﬂow applications. Examples of ﬂows involving such interactions are the ﬂows over deﬂected control surfaces or inside super- and hypersonic engine inlets. A key feature of

Get Price### Shock-unsteadiness model applied to oblique shock wave

International Journal of Computational Fluid Dynamics Vol. 22 No. 8 September 2008 569–582 Shock-unsteadiness model applied to oblique shock wave/turbulent boundary-layer interaction Amjad Ali Pasha and Krishnendu Sinha Department of Aerospace Engineering Indian Institute of Technology Bombay Mumbai India (Received 26 December 2007

Get Price### Low-Frequency Unsteadiness in DNS of Shock

The interaction of a shock wave with a turbulent boundary layer (STBLI) is ubiquitous in compressible ﬂow applications. Examples of ﬂows involving such interactions are the ﬂows over deﬂected control surfaces or inside super- and hypersonic engine inlets. A key feature of

Get Price### Journal of Fluid Mechanics Lowfrequency unsteadiness in

The low-frequency unsteadiness is characterized in the direct numerical simulation of a shock wave–turbulent boundary layer interaction generated by a 24compression ramp in Mach 2.9 ﬂow.

Get Price### Characterization of an incipiently separated shock wave

The turbulence structure in a shock wave/turbulent boundary layer interaction at incipient separation was investigated in order to get insight into turbulence generation and amplification mechanisms in such flow fields. Low-frequency unsteadiness of shock wave/turbulent boundary layer interactions. Annu. Rev. Fluid Mech. 46 A. Dussauge

Get Price### Simulation of Hypersonic Shock/Turbulent Boundary-Layer

which neglect the shock-unsteadiness damping effect overly amplify the TKE across a shock wave. Sinha et al. 10 applied the shock-unsteadiness modiﬁcation to commonly used one- and two-equation turbulence models like the k- k- andSpalart–Allmarasmodels. Theimplementation issuch

Get Price### Sensitivity analysis for the control of oblique shock wave

ble for the unsteadiness. Dupont et al.15 points to coherence between wall pressure uctuations at the foot of the re ected shock and in the reattachment zone for a turbulent SWBLI. This corresponds to the breathing character of the separation bubble. A simple model based on

Get Price### NASA Technical Reports Server (NTRS)

Fluctuations and massive separation in three-dimensional shock-wave/boundary-layer interactions Shock-wave unsteadiness was observed in rapidly compressed supersonic turbulent boundary layer flows with significant separation. A Mach 2.85 shock-wave/turbulent boundary layer flow was set up over a series of cylinder-flare bodies in the High Reynolds Number Channel 1.

Get Price### Dynamics of swept shock-wave/turbulent-boundary-layer

Swept shock-wave/turbulent-boundary-layer interactions (STBLIs) exhibit key dynamical differences from their spanwise-homogeneous counterparts including the suppression of a dominant mechanism of low-frequency unsteadiness.

Get Price### Low-Frequency Unsteadiness of Shock Wave/Turbulent

Shock wave/boundary layer interactions occur in a wide range of supersonic internal and external flows and often these interactions are associated with turbulent boundary layer separation. The resulting separated flow is associated with large-scale low-frequency unsteadiness whose cause has been the subject of much attention and debate. In particular some researchers have concluded that the

Get Price### Low-Frequency Unsteadiness of Shock Wave/Turbulent

Shock wave/boundary layer interactions occur in a wide range of supersonic internal and external flows and often these interactions are associated with turbulent boundary layer separation. The resulting separated flow is associated with large-scale low-frequency unsteadiness whose cause has been the subject of much attention and debate.

Get Price### Low-Frequency Unsteadiness of Shock Wave/Turbulent

Shock wave/boundary layer interactions occur in a wide range of supersonic internal and external flows and often these interactions are associated with turbulent boundary layer separation. The resulting separated flow is associated with large-scale low-frequency unsteadiness whose cause has been the subject of much attention and debate. In particular some researchers have concluded that the

Get Price### Modeling the Effect of Shock Unsteadiness in Shock

Interaction with a shock wave enhances the turbulent ﬂuctuations in a ﬂow. Sinha et al.6 propose the following model for the ampliﬁ-cation of k and across a shock wave k 2/k 1 = (u˜ n 1/u˜ n 2) 2 3 (1−b 1) 2/ 1 = (u˜ n 1/u˜ n 2) c 1 where b 1 represents the effect of the shock-unsteadiness given by (3) and c 1 =1.25 0.2(M 1n

Get Price### Modeling the Effect of Shock Unsteadiness in Shock-Wave

Shock-unsteadiness modi cation to the k- and k- models Sinha et al.7 applied the k- model to the interac-tion of homogeneous isotropic turbulence with a nor-mal shock wave. They showed that the model exces-sively ampli es the turbulent kinetic energy through the shock. This is due to the fact that the production of k given by Pk = T(2SijSji 2

Get Price### Modeling the Effect of Shock Unsteadiness in Shock-Wave

Shock-unsteadiness modi cation to the k- and k- models Sinha et al.7 applied the k- model to the interac-tion of homogeneous isotropic turbulence with a nor-mal shock wave. They showed that the model exces-sively ampli es the turbulent kinetic energy through the shock. This is due to the fact that the production of k given by Pk = T(2SijSji 2

Get Price### Application of a dual-plane particle image velocimetry

Application of a dual-plane particle image velocimetry (dual-PIV) technique for the unsteadiness characterization of a shock wave turbulent boundary layer

Get Price### Modeling the effect of shock unsteadiness in shock-wave

This may be because RANS models do not account for the unsteady motion of the shock wave that is inherent in these interactions. Sinha et al. Phys. Fluids Vol. 15 No. 8 (2003) propose a shock-unsteadiness correction that significantly improves turbulence prediction across a normal shock in a uniform mean flow.

Get Price### Characterization of an incipiently separated shock wave

The turbulence structure in a shock wave/turbulent boundary layer interaction at incipient separation was investigated in order to get insight into turbulence generation and amplification mechanisms in such flow fields. Low-frequency unsteadiness of shock wave/turbulent boundary layer interactions. Annu. Rev. Fluid Mech. 46 A. Dussauge

Get Price### A Phenomenological Model for Turbulent Heat Flux in High

Jan 09 2018 · The shock-unsteadiness (SU) k– ω model is used as the baseline since it gives good prediction of flow separation and the regions of APG. The new model gives marked improvement in the peak heat flux prediction near the reattachment point. The

Get Price### Large-eddy simulation of low-frequency unsteadiness in a

The need for better understanding of the low-frequency unsteadiness observed in shock wave/turbulent boundary layer interactions has been driving research in this area for several decades. We present here a large-eddy simulation investigation of theinteraction between an impinging oblique shock and a Mach 2.3 turbulent boundary layer.

Get Price### Conditional Analysis of a Shock Wave and Turbulent

versity of Maryland College Park — The characterization of the aperiodic cycle of unsteadiness in shock wave and turbulent boundary layer interaction (STBLI) is presented for a 24 compression ramp conﬁguration with a fully turbulent incoming boundary layer at Mach 2.9. In previous work on the direct numerical simulation

Get Price### Application of a dual-plane particle image velocimetry

Application of a dual-plane particle image velocimetry (dual-PIV) technique for the unsteadiness characterization of a shock wave turbulent boundary layer

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