Nose-Tip Bluntness Effects on Transition at Hypersonic Speeds

Paredes, Pedro; Choudhari, Meelan M.; Li, Fēi; Jewell, Joseph S.; Kimmel, Roger L.; Marineau, Eric C.; Grossir, Guillaume

doi:10.2514/1.a34277

Cited by 80 publications

(20 citation statements)

References 65 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…First, as could already be seen in the results of figure 7, at the higher altitude the maximum value reached by is larger: the value reached at m at altitude km is , which corresponds to an equivalent -factor (Paredes et al. 2019) Such -factor values are typically associated with laminar–turbulent transition of stationary crossflow vortices in the incompressible regime (Bippes 1999) and are certainly considered sufficiently high to lead the laminar flow to transition. In the present analysis, algebraically-growing perturbations are demonstrated to also reach through the alternative non-modal linear instability mechanism that potentially can be responsible for transition; we will return to the question of the associated structures, quantified as linear optimal perturbations, in what follows.…”

Section: Resultsmentioning

confidence: 78%

Transient growth analysis of hypersonic flow over an elliptic cone

et al. 2022

Self Cite

View full text Add to dashboard Cite

Non-modal linear stability analysis results are presented for hypersonic flow over an elliptic cone with an aspect ratio of two at zero angle of attack, completing earlier modal instability analysis of flow around the same geometry. The theoretical framework to perform transient growth analysis of compressible flows on a generalized two-dimensional frame of reference is developed for the first time and is then applied to solve the initial-value problem governing non-modal linear instability on planes perpendicular to the cone axis, taken at successive streamwise locations along the elliptic cone. Parameter ranges examined here are chosen so as to model flight of the Hypersonic International Flight Research Experimentation 5 (HIFiRE-5) test geometry at altitudes of 21 km and 33 km, corresponding to Mach numbers 7.45 and 8.05 and unit Reynolds numbers $Re' = 1.07\times 10^7$ and $1.89\times 10^6$ , respectively. Results obtained indicate that the significance of the non-modal growth for laminar–turbulent transition increases with increasing flight altitude (decreasing Reynolds number). At a given set of flow parameters, transient growth is stronger in the vicinity of the tip of the cone and in azimuthal locations away from both of the minor (centreline) and major (attachment line) axes of the cone. Linear optimal disturbances calculated at conditions of maximal transient growth are found to peak in the crossflow region of the elliptic cone. These structures are elongated along the streamwise spatial direction, while being periodic along the spanwise direction with periodicity lengths of the same order of magnitude as the well-known structures identified as crossflow vortices in both experiments and simulations.

show abstract

Section: Resultsmentioning

confidence: 78%

Transient growth analysis of hypersonic flow over an elliptic cone

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…原因造成了转捩, 也有人猜测是瞬态增长、头部粗糙度或二者共同的结果 [27] . 虽然高超声速钝头体边界层转捩的机理还有待探索, 但实际飞行器通常都是钝头体, 飞行器设计时迫切需要预测转捩位置.…”

Section: 有人认为线性稳定性理论已经失效可能是别的未知unclassified

Investigation on correlation between wind tunnel and flight for boundary layer stability and transition of MF-1 blunt cone

Wan

Chen

et al. 2019

Sci. Sin.-Phys. Mech. Astron.

View full text Add to dashboard Cite

“…The second kind of factor influencing hypersonic boundary layer receptivity is wall disturbances, including blow-suction disturbances [ 15 ], wall deformation [ 16 ], local heating/cooling on the wall [ 17 ], and nose-tip bluntness [ 18 , 19 ]. The effect of roughness elements on the hypersonic boundary layer receptivity mechanism has been researched.…”

Section: Introductionmentioning

confidence: 99%

Effect of a Roughness Element on the Hypersonic Boundary Layer Receptivity Due to Different Types of Free-Stream Disturbance with a Single Frequency

Shi

Wang

et al. 2019

Entropy

View full text Add to dashboard Cite

The hypersonic flow field around a blunt cone was simulated using a high-order finite difference method. Fast acoustic waves, slow acoustic waves, entropy waves, and vortical waves were introduced into the free-stream to determine the influence of a free-stream with disturbances on the hypersonic flow field and boundary layer. The effect of disturbance type on the evolution of perturbations in the hypersonic boundary layer was analyzed. Fast Fourier Transform was adopted to analyze the effect of the disturbance type on the evolution of different modes in the boundary layer. A roughness element was introduced into the flow field to reveal the impact of the roughness element on hypersonic boundary layer receptivity. The results showed that a free-stream with disturbances affected the hypersonic flow field and boundary layer; acoustic waves had the greatest influence. The impact of slow acoustic waves on the flow field was mainly concentrated in the region between the shock and the boundary layer, whereas the influence of fast acoustic waves was mainly concentrated in the boundary layer. Multi-mode perturbations formed in the boundary layer were caused by the free-stream with disturbances, wherein the fundamental mode was the dominant mode of the perturbations in the boundary layer caused by fast acoustic waves, entropy waves, and vortical waves. The dominant modes of the perturbations in the boundary layer caused by slow acoustic waves were both the fundamental mode and the second harmonic mode. The roughness element changed the propagation process of different modes of perturbations in the boundary layer. In the downstream region of the roughness element, perturbations in the boundary layer caused by the slow acoustic waves had the greatest influence. The second harmonic mode in the boundary layer was significantly suppressed, and the fundamental mode became the dominant mode. The effects of fast acoustic waves and entropy waves on the boundary layer receptivity were similar, except the amplitude of the perturbations in the boundary layer caused by the fast acoustic waves was larger.

show abstract

Nose-Tip Bluntness Effects on Transition at Hypersonic Speeds

Cited by 80 publications

References 65 publications

Transient growth analysis of hypersonic flow over an elliptic cone

Transient growth analysis of hypersonic flow over an elliptic cone

Investigation on correlation between wind tunnel and flight for boundary layer stability and transition of MF-1 blunt cone

Effect of a Roughness Element on the Hypersonic Boundary Layer Receptivity Due to Different Types of Free-Stream Disturbance with a Single Frequency

Contact Info

Product

Resources

About