NASA Langley Mach 6 quiet wind-tunnel performance

Blanchard, A.; Lachowicz, Jason T.; Wilkinson, Stephen

doi:10.2514/3.13459

Cited by 8 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Beyond this quiet core region is a low-noise region within which hot-wire measurements show a continuous spectrum with no coherent peaks. 13 The boundary layer measurements were obtained on an 18 in. long sharp tip cone with a curved-flare afterbody, Fig.…”

Section: Test Facility and Modelmentioning

confidence: 99%

Nonlinear spectral dynamics of hypersonic laminar boundary layer flow

Chokani

1999

Physics of Fluids

View full text Add to dashboard Cite

Articles you may be interested inA high-order numerical method to study hypersonic boundary-layer instability including high-temperature gas effects Phys. Fluids 23, 084108 (2011); 10.1063/1.3614526On the relationship between the wall-shear-stress and transient-growth disturbances in a laminar boundary layerThe nonlinear interactions of the instability modes in a hypersonic laminar boundary layer undergoing natural transition are examined using bispectral analysis. The data are from an experiment of a boundary layer flow on a cooled-wall cone in a low-level free-stream disturbance hypersonic wind tunnel, and thus, the bispectral measurements are a good representation of the natural transition processes. The bispectral analysis shows that in the initial stages of transition the dominant nonlinear interaction is forcing by the fundamental to generate a harmonic. Subsequently, mutual forcing of the fundamental and harmonic yield a second harmonic. Difference interactions within the band of unstable disturbances centered on the fundamental and harmonic also generate a low frequency nonlinear interaction. At high amplitudes of the fundamental and harmonic a nonlinear interaction characterized by a low frequency modulation of the fundamental and harmonic then follows. This nonlinear interaction is then the most dominant and precedes the breakdown of the laminar flow.

show abstract

Section: Test Facility and Modelmentioning

confidence: 99%

Nonlinear spectral dynamics of hypersonic laminar boundary layer flow

Chokani

1999

Physics of Fluids

View full text Add to dashboard Cite

show abstract

“…The profile is typically characterized by an exponential rise in pressure, an immediate decrease below the nominal Pitot pressure, and an exponential recovery back to the nominal pressure. This profile occurs in approximately 1-2 ms, and directly follows the general character of the sound-mode disturbances described in Blanchard (1997) To quantify the variation in the occurrence density of these intermittencies, an 'intermittency factor' was defined as the percentage of moving-RMS windows (2 ms wide) within a larger traveling window (1000 ms wide) found to contain an RMS level greater than a threshold. The moving RMS and intermittency factor are plotted together for this run in Figure 7.…”

Section: Determination Of Upper Pressure Limit For Quiet Flowmentioning

confidence: 88%

Experiments on Transition Physics in Hypersonic Boundary Layers: Validation Data for Modeling and Computations

Saric¹

2012

View full text Add to dashboard Cite

PubliC reportmg burden for this collection of information 1 s estimated to average 1 hour per response . including the t1me for rev1ewing mstructlons. searchmg ex1 sting data sources . gathenng and ma1 ntaimng the data needed. and com ple ting and rev1 ev.1ng this collect1on o f information Send comments regard1ng this burden e stimate or any other aspect of th1s collect1on o f informa ti on. includ1ng suggesti ons fo r reducmg The Mach 6 Quiet Tunnel (M6QT) , the hypersonic low-disturbance facility formerly at NASA Langley, has been permanently installed as part of the Texas A&M National Aerothermochemistry Laboratory (TAMU-NAL) in College Station, Texas. The tunnel now operates interchangeably with the Adaptively Controlled Expansion Mach 5-8 tunnel (ACE) in a blowdown configuration with a maximum runtime of approximately 50 seconds. An initial series of tests to determine the quiet-flow capabilities of the nozzle indicate performance largely consistent with its former operation at NASA Langley, with evidence of a full-length quiet test core at stagnation pressures up to 145 psia. Intermittency present in the pressure signals at total pressures above 80 psia is quantified and discussed. In addition, the capability of the tunnel to support future flared-cone experimental models is demonstrated.

show abstract

“…Growth of first and second-mode instability waves was observed on an axisymmetric cone under cold-flow conditions, in a quiet tunnel [78]. An adverse pressure gradient exists on the rear half of the model.…”

Section: Sharp Flared Cone At Machmentioning

confidence: 93%

Hypersonic laminar instability on round cones near zero angle of attack

Schneider

2001

39th Aerospace Sciences Meeting and Exhibit

View full text Add to dashboard Cite

Reliable predictions for hypersonic laminarturbulent transition will have to be based on simulation of the transition mechanisms. Accurate simulation of the second-mode instability-wave growth on a round cone at zero angle of attack would be a significant step toward this goal. Hypersonic stability experiments in this geometry are reviewed, and three are selected. Extensive and previously unpublished data from Stetson's sharp and blunt cone experiments are reported. Approximate computations were carried out using inviscid-boundary-layer and e N methods. The experimental results are compared to previous high-accuracy computations and to the present approximate computations. Quantitative agreement is at present insufficient for reliable e N predictions. The difficulties with both experiment and computation are described.

show abstract

NASA Langley Mach 6 quiet wind-tunnel performance

Cited by 8 publications

References 0 publications

Nonlinear spectral dynamics of hypersonic laminar boundary layer flow

Nonlinear spectral dynamics of hypersonic laminar boundary layer flow

Experiments on Transition Physics in Hypersonic Boundary Layers: Validation Data for Modeling and Computations

Hypersonic laminar instability on round cones near zero angle of attack

Contact Info

Product

Resources

About