Combined free-stream disturbance measurements and receptivity studies in hypersonic wind tunnels by means of a slender wedge probe and direct numerical simulation
Authors
Wagner, AlexanderSchülein, Erich
Petervari, René
Hannemann, Klaus
Ali, Syed RC
Cerminara, Adriano
Sandham, Neil D
Issue Date
2018-03-13
Metadata
Show full item recordAbstract
Combined free-stream disturbance measurements and receptivity studies in hypersonic wind tunnels were conducted by means of a slender wedge probe and direct numerical simulation. The study comprises comparative tunnel noise measurements at Mach 3, 6 and 7.4 in two Ludwieg tube facilities and a shock tunnel. Surface pressure fluctuations were measured over a wide range of frequencies and test conditions including harsh test environments not accessible to measurement techniques such as Pitot probes and hot-wire anemometry. A good agreement was found between normalized Pitot pressure fluctuations converted into normalized static pressure fluctuations and the wedge probe readings. Quantitative results of the tunnel noise are provided in frequency ranges relevant for hypersonic boundary-layer transition. Complementary numerical simulations of the leading-edge receptivity to fast and slow acoustic waves were performed for the applied wedge probe at conditions corresponding to the experimental free-stream conditions. The receptivity to fast acoustic waves was found to be characterized by an early amplification of the induced fast mode. For slow acoustic waves an initial decay was found close to the leading edge. At all Mach numbers, and for all considered frequencies, the leading-edge receptivity to fast acoustic waves was found to be higher than the receptivity to slow acoustic waves. Further, the effect of inclination angles of the acoustic wave with respect to the flow direction was investigated. An inclination angle was found to increase the response on the wave-facing surface of the probe and decrease the response on the opposite surface for fast acoustic waves. A frequency-dependent response was found for slow acoustic waves. The combined numerical and experimental approach in the present study confirmed the previous suggestion that the slow acoustic wave is the dominant acoustic mode in noisy hypersonic wind tunnels.Citation
Wagner, A., Schülein, E., Petervari , R. and Hannemann, K. (2018) Combined free-stream disturbance measurements and receptivity studies in hypersonic wind tunnels by means of a slender wedge probe and direct numerical simulation, Journal of Fluid Mechanics, 842, pp. 495-531.Publisher
Cambridge University Press (CUP)Journal
Journal of Fluid MechanicsType
Journal articleLanguage
enISSN
0022-1120EISSN
1469-7645Sponsors
The present study was supported by an ESA funded Technology Research Project (ESA-Contract number $4200022793/09/NL/CP$).ae974a485f413a2113503eed53cd6c53
10.1017/jfm.2018.132
Scopus Count
Collections
Except where otherwise noted, this item's license is described as https://creativecommons.org/licenses/by-nc-sa/4.0/