Flowfield of a 3-D Swept Shock Boundary Layer Interaction in a Mach 2 Flow

Arora, Nishul; Ali, Mohd Y.; Alvi, Farrukh S.

doi:10.2514/6.2016-3649

Cited by 27 publications

(9 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1). Among these is the interaction quasi-conical symmetry, which is exhibited for all simulations of the present work, consistent with experimental observation [37,40]. Within this quasisymmetry, the flow is approximately independent of the radial coordinate of a spherical coordinate system emanating from the virtual conical origin (VCO).…”

Section: Flow Structuresupporting

confidence: 90%

“…Several interesting trends with interaction strength are then assimilated in terms of dependence on the inceptive-origin/ virtual-conical-origin relationship. Validation results with the experiments of Vanstone et al [39,40] as well as Arora et al [37] and Baldwin et al [38] are purposefully deferred to Sec. III.E, to allow for discussion of the observations in the context of results elaborated in earlier sections.…”

Section: Introductionmentioning

confidence: 92%

“…The STBLIs examined consist of shocks generated from Mach 2 flow over SCRs and SFs. The flow conditions (Table 1) follow those of the SCR experiments of Vanstone et al [39] and the SF campaign of Arora et al [37] and Baldwin et al [38]. The simulation Reynolds number (Re) is reduced for computational feasibility.…”

Section: B Geometry Computational Grid and Boundary Conditionsmentioning

confidence: 99%

“…The above insights are now assimilated into the validation of the simulations. Validation for the SF configuration is undertaken with the experiments of Arora et al [37] and Baldwin et al [38] for 15°a ngle of attack. The experiments of Vanstone et al [39,40] are employed for validation of the SCR configuration with 30.0°sweep and 22.5°compression.…”

Section: E Experimental Validationmentioning

confidence: 99%

“…Aspects of unsteadiness that relate to the mean flow are also discussed, though for brevity, detailed discussions of spectra are deferred to a forthcoming paper. The simulations are grounded in parallel experimental campaigns for both the SF [37,38] and SCR [39,40] interactions. However, the present LES are not inhibited by the limitations of near-wall measurement resolution or fidelity, as are current experimental or RANS-based techniques, respectively.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Flow Similarity in Strong Swept-Shock/Turbulent-Boundary-Layer Interactions

Adler

Gaitonde

2019

AIAA Journal

View full text Add to dashboard Cite

The separation length employed to scale unsteady phenomena in strong (separated) nominally two-dimensional (2-D) shock/turbulent-boundary-layer interactions cannot be directly extended to three-dimensional (3-D) swept interactions, due to the quasi-conical symmetry of 3-D interactions. This paper examines the issue by considering large-eddy simulations of Mach 2 canonical flows arising from plate-mounted swept compression ramps and sharp fins at various interaction strengths, which have been the subject of concurrent experimental campaigns. Several key structural features are discussed that distinguish 3-D interactions from 2-D interactions in the context of free-interaction principles and quasi-conical symmetry, including their relationship to strong crossflow and open separation. The virtual-conical-origin concept is augmented by considering inceptive effects, which motivate the introduction of an inceptive origin. The dependence of the inceptive-origin/virtual-conical-origin relationship with interaction strength yields several insights and provides a more rigorous framework to quantify inception strength than previously available. Finally, examination of the spanwise dependence of the growth of the quasi-conical separated shear layer shows that the outer (main) layer exhibits spanwise-homogeneous symmetry consistent with 2-D free-interaction theory, whereas the inner layer exhibits conical symmetry, consistent with 3-D (conical) free-interaction theory. The ramifications for shear layer and shock unsteadiness, as well as acceleration of the inner layer and secondary separation, are discussed. Recent developments and persisting fundamental challenges are discussed by Clemens and Narayanaswamy [2] and Gaitonde [3]. Significant insight has been gained through recent experimental and high-fidelity numerical efforts for canonical two-dimensional (2-D) configurations, which are spanwise homogeneous apart from side-wall effects. These include the impinging shock [4-7] and compression ramp [8,9] interactions. Comparatively less attention has been focused on the unsteady properties of canonical three-dimensional (3-D) STBLIs. These include configurations for which the mean flow is 3-D; that is, interactions that exhibit spanwise nonhomogeneity caused by the geometry/orientation of the shock generator which cannot be attributed to edge/side-wall effects. Specifically, interactions in which the shock or obstacle is swept with respect to the incoming flow are of interest. These include the sharp-fin (SF), swept-compression-ramp (SCR), and swept-impinging-shock (SIS) configurations, as commonly described [3,10]. Such interactions are of particular concern in application to supersonic/hypersonic inlets with side-wall compression, because side-wall compression may be exploited to increase the total pressure recovery [11,12]. More complex scenarios include flows with multiple interactions (shock trains) in scramjet inlet/ isolator sections, which highlight complexities associated with the dynamic coupling between canonical i...

show abstract

Section: Flow Structuresupporting

confidence: 90%

Section: Introductionmentioning

confidence: 92%

Section: B Geometry Computational Grid and Boundary Conditionsmentioning

confidence: 99%

Section: E Experimental Validationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Flow Similarity in Strong Swept-Shock/Turbulent-Boundary-Layer Interactions

Adler

Gaitonde

2019

AIAA Journal

View full text Add to dashboard Cite

show abstract

Influence of separation structure on the dynamics of shock/turbulent-boundary-layer interactions

Adler

Gaitonde

2021

Theor. Comput. Fluid Dyn.

View full text Add to dashboard Cite

Shock/turbulent-boundary-layer interactions (STBLIs) are ubiquitous in high-speed flight and propulsion applications. Experimental and computational investigations of swept, three-dimensional (3-D) interactions, which exhibit quasi-conical mean-flow symmetry in the limit of infinite span, have demonstrated key differences in unsteadiness from their analogous, two-dimensional (2-D), spanwise-homogeneous counterparts. For swept interactions, represented by the swept–fin-on-plate and swept–compression–ramp-on-plate configurations, differences associated with the separated shear layers may be traced to the intermixing of 2-D (spanwise independent) and 3-D (spanwise dependent) scaling laws for the separated mean flow. This results in a broader spectrum of unsteadiness that includes relatively lower frequencies associated with the separated shear layers in 3-D interactions. However, lower frequency ranges associated with the global “breathing” of strongly separated 2-D interactions are significantly less prominent in these simple, swept 3-D interactions. A logical extension of 3-D interaction complexity is the compound interaction formed by the merging of two simple interactions. The first objective of this work is therefore to analyze the more complex picture of the dynamics of such interactions, by considering as an exemplar, wall-resolved simulations of the double-fin-on-plate configuration. We show that in the region of interaction merging, new flow scales, changes in separation topology, and the emergence of lower-frequency phenomena are observed, whereas the dynamics of the interaction near the fin leading edges are similar to those of the simple, swept interactions. The second objective is to evolve a unified understanding of the dynamics of STBLIs associated with complex configurations relevant to actual propulsion systems, which involve the coupling between multiple shock systems and multiple flow separation and attachment events. For this, we revisit the salient aspects of scaling phenomena in a manner that aids in assimilating the double-fin flow with simpler swept interactions. The emphasis is on the influence of the underlying structure of the separated flow on the dynamics. The distinct features of the compound interactions manifest in a centerline symmetry pattern that replaces the quasi-conical symmetry of simple interactions. The primary separation displays topological closure to reveal new length scales, associated unsteadiness bands, and secondary flow separation.

show abstract