Spatial Direct Numerical Simulation of the Hypersonic Boundary-Layer Stabilization Using Porous Coatings

Zhao, Rui; Wen, Chih-Yung; Long, Tiehan; Tian, Xudong; Zhou, Lin; Wu, Yue

doi:10.2514/1.j058467

Cited by 33 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Computational studies have long proven their ability to capture the UAC stabilizing effect by either directly resolving the flow inside the porous coating [22][23][24][25][26] or by modeling its impedance as a boundary condition [27][28][29][30][31]. The direct numerical simulation (DNS) of Brès et al [22] resolved the UAC damping effects using the former method by meshing the pores as uniformly-spaced cavities.…”

Section: Introductionmentioning

confidence: 99%

Numerical Analysis of Porous Coatings Stabilizing Capabilities on Hypersonic Boundary-Layer Transition

et al. 2021

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Numerical Analysis of Porous Coatings Stabilizing Capabilities on Hypersonic Boundary-Layer Transition

et al. 2021

View full text Add to dashboard Cite

“…The impedance model could generally represent the effect of realistic metasurface microstructures for the first mode, but the results are not consistent with the comparisons for the Mack second mode [37].…”

Section: Dns Verificationmentioning

confidence: 66%

“…In the above LST analyses, the impedance boundary condition was applied to represent the acoustic effect of the real microstructures on the BL but ignored the recirculation flows inside the slits and the alternating expansion and compression waves induced at the slit edges [37] (Fig. 10).…”

Section: Dns Verificationmentioning

confidence: 99%

See 1 more Smart Citation

Broadband Design of Acoustic Metasurfaces for the Stabilization of a Mach 4 Boundary Layer Flow

Zhao

Xiao

Wen

et al. 2021

Preprint

View full text Add to dashboard Cite

A piecewise acoustic metasurface is designed to suppress the first mode while marginally amplifying the Mack second mode in a Mach 4 flat-plate boundary layer (BL) flow. The results of linear stability theory (LST) and the eN method demonstrate the stabilization effect and transition delay performance, respectively. However, the direct numerical simulation (DNS) results indicate that the designed broadband acoustic metasurface actually weakly excites the first mode with a slightly larger fluctuating pressure amplitude at the surface, which is in contrast to the analysis of LST. The discrepancies are found to lie in the ‘roughness’ effect caused by the recirculation zones inside the microslits and the alternating expansion and compression waves induced at the slit edges, which significantly amplifies the first mode. For further clarification of the competitive mechanism between the acoustic stabilization and ‘roughness’ destabilization effects of metasurfaces on the first mode, a carefully designed metasurface is installed at the maximum growth rate region, which excites the first mode on the metasurface but inhibits its development downstream.

show abstract

“…Computational studies have also been able to capture the UAC stabilizing effect by either directly resolving the porous coating 21,22 or by modeling its impedance as a boundary condition. [23][24][25][26][27] The direct numerical simulation (DNS) of Brès et al 21 resolved the UAC damping effects using the former method by meshing the pores as uniformly-spaced cavities.…”

Section: Introductionmentioning

confidence: 99%

Numerical Study of Hypersonic Boundary-Layer Transition Delay through Second-Mode Absorption

Fiévet¹,

Deniau²,

Brazier³

et al. 2020

AIAA Scitech 2020 Forum

View full text Add to dashboard Cite

Numerical time-domain impedance boundary conditions are developed within a highorder spectral difference flow solver. They are designed to accurately replicate the acoustic response of ultrasonically-absorbent coatings over a broad spectral range. The coupling of this class of high-fidelity wall boundary conditions with high-order numerical methods has enabled their use in aero-acoustics applications. This solver is used to perform direct numerical simulations (DNS) of a hypersonic boundary layer and analyze the stabilizing effects of acoustically absorbent materials on the laminar-to-turbulent transition. The damping effectiveness of such complex porous coating on key frequencies of interest is investigated, as well as its effect on the mean flow. It is found that the second-mode instability, which dominates the high-Mach number flow regime, is strongly suppressed at the expense of higher far-field noise radiation. The solutions obtained by means of DNS are also found to compare favorably with linearized stability theory.

show abstract

Spatial Direct Numerical Simulation of the Hypersonic Boundary-Layer Stabilization Using Porous Coatings

Cited by 33 publications

References 21 publications

Numerical Analysis of Porous Coatings Stabilizing Capabilities on Hypersonic Boundary-Layer Transition

Numerical Analysis of Porous Coatings Stabilizing Capabilities on Hypersonic Boundary-Layer Transition

Broadband Design of Acoustic Metasurfaces for the Stabilization of a Mach 4 Boundary Layer Flow

Numerical Study of Hypersonic Boundary-Layer Transition Delay through Second-Mode Absorption

Contact Info

Product

Resources

About