Measurements and correlations of transition Reynolds numbers on sharp slender cones at high speeds

Pate, S. R.

doi:10.2514/6.1970-799

Cited by 8 publications

(5 citation statements)

References 4 publications

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“…Clarification of the transition mechanism and prediction of the transition have been attempted and numerous studies have been conducted analytically, numerically and experimentally. [1][2][3][4][5][6][7] It is known that several factors affect the transition. The transition Reynolds number increases with increases in Mach number and unit Reynolds number.…”

Section: Introductionmentioning

confidence: 99%

Conservation-Law Approach to Prediction of Boundary Layer Transition

Kanda¹

2011

Trans. Japan Soc. Aero. S Sci.

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The boundary layer transition is predicted using the law of mass conservation. The increasing ratio of the boundary layer thickness to the laminar boundary layer thickness at the transition is introduced. Formulas and equations for laminar and turbulent boundary layers are used to predict the transition Reynolds number. The effect of the momentum deficit at the leading edge is also incorporated in this approach under compressible flow conditions. The calculated transition Reynolds number shows reasonable agreement with the experimental results. Under the compressible flow conditions, the calculation simulates the bucket of the transition Reynolds number with a Mach number, the change in the transition Reynolds number due to wall cooling, and the increase in the transition Reynolds number with increase in the bluntness Reynolds number.

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Section: Introductionmentioning

confidence: 99%

Conservation-Law Approach to Prediction of Boundary Layer Transition

Kanda¹

2011

Trans. Japan Soc. Aero. S Sci.

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“…[1][2][3][4][5][6][7][8][9][10][11][12][13] The elevated freestream disturbance levels in conventional (i.e., noisy) high-speed wind tunnels usually result in an earlier onset of transition relative to that in a flight environment or in a quiet tunnel. Yet, the conventional facilities continue to be used for transition sensitive measurements because of the size and Reynolds number limitations of existing quiet facilities and the prohibitive cost of flight tests.…”

Section: Introductionmentioning

confidence: 99%

Numerical Study of Pressure Fluctuations due to a Mach 6 Turbulent Boundary Layer

Duan

Choudhari

2013

51st AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition

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Direct numerical simulations (DNS) are used to examine the pressure fluctuations generated by a Mach 6 turbulent boundary layer with nominal freestream Mach number of 6 and Reynolds number of Reτ ≈ 464. The emphasis is on comparing the primarily vortical pressure signal at the wall with the acoustic freestream signal under higher Mach number conditions. Moreover, the Mach-number dependence of pressure signals is demonstrated by comparing the current results with those of a supersonic boundary layer at Mach 2.5 and Reτ ≈ 510. It is found that the freestream pressure intensity exhibits a strong Mach number dependence, irrespective of whether it is normalized by the mean wall shear stress or by the mean pressure, with the normalized fluctuation amplitude being significantly larger for the Mach 6 case. Spectral analysis shows that both the wall and freestream pressure fluctuations of the Mach 6 boundary layer have enhanced energy content at high frequencies, with the peak of the premultiplied frequency spectrum of freestream pressure fluctuations being at a frequency of ωδ/U∞ ≈ 3.1, which is more than twice the corresponding frequency in the Mach 2.5 case. The space-time correlations indicate that the pressure-carrying eddies for the higher Mach number case are of smaller size, less elongated in the spanwise direction, and convect with higher convection speeds relative to the Mach 2.5 case. The demonstrated Mach-number dependence of the pressure field, including radiation intensity, directionality, and convection speed, is consistent with the trend exhibited in experimental data and can be qualitatively explained by the notion of 'eddy Mach wave' radiation. NomenclatureC p heat capacity at constant pressure, J/(K·kg) C pp Space-time correlation coefficient of the pressure field, dimensionless C v heat capacity at constant volume, J/(K·kg)

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“…Since Pate had measured the end of transition, as defined here, it was necessary to take the beginning of transition from axial pitot traverses presented in Ref. 11. A large quantity of this type of data was, understandably, not available; therefore, the extent of the comparison is not extensive.…”

Section: Comparisons In Other Flow Regimesmentioning

confidence: 99%

A Method for the Prediction of the Effects of Free-Stream Disturbances on Boundary-Layer Transition

Benek¹,

High²

1973

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A semiempirical expression for boundary-layer transition location is developed based on the concept of a critical ratio of inertial to viscous shearing stresses at laminar breakdown. Extensive comparisons between predicted and measured transition locations on a 10-deg included-angle cone at transonic speeds are shown with the data predicted to within 10 percent. Comparisons are also made with low subsonic and supersonic data which indicate the method is extendible to these flow regimes.

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Measurements and correlations of transition Reynolds numbers on sharp slender cones at high speeds

Cited by 8 publications

References 4 publications

Conservation-Law Approach to Prediction of Boundary Layer Transition

Conservation-Law Approach to Prediction of Boundary Layer Transition

Numerical Study of Pressure Fluctuations due to a Mach 6 Turbulent Boundary Layer

A Method for the Prediction of the Effects of Free-Stream Disturbances on Boundary-Layer Transition

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