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A new wind tunnel for the study of pressure-induced separating and reattaching flows

Published online by Cambridge University Press:  27 January 2016

A. Mohammed-Taifour ,
Q. Schwaab ,
J. Pioton  and
J. Weiss
A. Mohammed-Taifour
Affiliation:
Laboratoire TFT, École de technologie supérieure, Montréal, Québec, Canada
Q. Schwaab
Affiliation:
Laboratoire TFT, École de technologie supérieure, Montréal, Québec, Canada
J. Pioton
Affiliation:
Laboratoire TFT, École de technologie supérieure, Montréal, Québec, Canada
J. Weiss*
Affiliation:
Laboratoire TFT, École de technologie supérieure, Montréal, Québec, Canada
*
[email protected]
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Abstract

The design, construction, and validation of a new academic wind tunnel is described in detail. The wind tunnel is of a classical, blow-down type and generates a pressure-induced, turbulent separation bubble on a flat test surface by a combination of adverse and favorable pressure gradients. The Reynolds number, based on momentum thickness just upstream of separation, is Reθ ≃ 5,000 at a free-stream velocity of Uref = 25ms−1. The length of the separation bubble is estimated at 0°42 ± 0°02m by three different methods. Results of a numerical simulation demonstrate the absence of flow separation in the wind-tunnel contraction. This results in a turbulence level of about 0·05% in the test section. Oil-film visualisation experiments show that the flow near the wall is strongly three-dimensional in the recirculating region and that the topology of the limiting streamlines is consistent with experiments performed on configurations with fixed separation. Finally, spatial variations of the forward-flow fraction have been documented using a thermal-tuft probe and are shown to compare well with the results of the oil-film visualisation.

Type
Research Article
Information
The Aeronautical Journal , Volume 119 , Issue 1211 , January 2015 , pp. 91 - 108
Copyright
Copyright © Royal Aeronautical Society 2015

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References

1.Amitay, M., Pitt, D. and Glezer, A.Separation control in duct flows, J Aircraft, 2002, 39, (4), pp 616–620.CrossRefGoogle Scholar
2.Barlow, J.B., Rae, W.H. and Pope, A.Low-Speed Wind Tunnel Testing, John Wiley & Sons, 3rd ed, 1999.Google Scholar
3.Blair, M.F., Bailey, D.A. and Schlinker, R.H. Development of a large-scale wind tunnel for the simulation of turbomachinery airfoil boundary layers, J Engineering for Gas Turbines and Power, 1981, (1034), pp 678–687.CrossRefGoogle Scholar
4.Bouriga, M, Lemyre-Baron, J.-S. F.Morency, F. and Weiss, J.Preliminary experimental and numerical investigations of the flow in the contraction of a boundary-layer wind tunnel, Transactions of the Canadian Society for Mechanical Engineering, 2014, 38, (4), pp 517–532.CrossRefGoogle Scholar
5.Bouriga, M., Taher, R., Morency, F. and Weiss, J. Numerical investigation of secondary flows in a constant-width wind-tunnel contraction, Aeronaut J (in press), 2015.CrossRefGoogle Scholar
6.Bradshaw, P.An introduction to turbulence and its measurement, Pergamon Press, 1971.Google Scholar
7.Bradshaw, P.Two more wind tunnels driven by aerofoil-type centrifugal blowers, Technical report, 72-10, Imperial College of Science and Technology, 1972.Google Scholar
8.Bradshaw, P. and Pankhurst, R.C.The design of low-speed wind tunnels, Progress in Aerospace Sciences, 1964, 5, pp 1–69.CrossRefGoogle Scholar
9.de Brederode, V. and Bradshaw, P.Three-dimensional fow in nominally two-dimensional separation bubbles: I. Flow behind a rearward-facing step, Technical report, 72-19, Imperial College of Science and Technology, 1972.Google Scholar
10.Cattafesta, L., Bahr, C. and Matthew, J.Fundamentals of Wind-Tunnel Design, Encyclopedia of Aerospace Engineering, John Wiley & Sons, 2010.CrossRefGoogle Scholar
11.Ciampoli, F. and Hancock, P.E.Effects of fow width in nominally two-dimensional turbulent separated flow, Experiments in Fluids, 2006, 40, pp 196–202.CrossRefGoogle Scholar
12.Clauser, F.H.Turbulent boundary layers in adverse pressure gradients, J Aeronautical Sciences, 1954, 21, (2), pp 91–108.CrossRefGoogle Scholar
13.Day, I.J.Stall inception in axial flow compressors, J Turbomachinery, 1993, 115, (1), pp 1–9.CrossRefGoogle Scholar
14.DeGraaff, D.B. and Eaton, J.K.Reynolds-number scaling of the flat-plate turbulent boundary layer, J Fluid Mechanics, 2000, 422, pp 319–346.CrossRefGoogle Scholar
15.Driver, D.M., Seegmiller, H.L. and Marvin, J.G.Time-dependent behavior of a reattaching shear layer, AIAA J, 1987, 25, (7), pp 914–919.CrossRefGoogle Scholar
16.Dussauge, J.-P., Dupont, P. and Debiève, J.-F.Unsteadiness in shock wave boundary layer interactions with separation, Aerospace Science and Technology, 2006, 10, (2), pp 85–91.CrossRefGoogle Scholar
17.Hancock, P.E. and Johnson, A.E.Close spacing of settling chamber screens, Aeronaut J, 1997, 101, (1004), pp 179–183.CrossRefGoogle Scholar
18.Hucho, W. and Sovran, G.Aerodynamics of road vehicles, Annual review of fluid mechanics, 1993, 25, (1), pp 485–537.CrossRefGoogle Scholar
19.Bell, J.H. and Metha, R.D.Boundary layer predictions for small low-speed contractions, AIAA J, 1989, 27, (3), pp 372–374.CrossRefGoogle Scholar
20.Jaroch, M.Oil flow visualization experiments in the separated and reattachment regions of the flow past a transverse flat plate with a long splitter plate, Zeitschrift für Flugwissenschaften und Weltraumforschung, 1987, 11, pp 230–236.Google Scholar
21.Johansson, A.V.A Low Speed Wind-Tunnel with Extreme Flow Quality – Design and Tests, pp 1603–1611, 1992, Proc. 18, bounceth ICAS Congress, Beijing, China.Google Scholar
22.Johnson, A.E. and Hancock, P.E.Some aspects of centrifugal fan characteristics in blower windtunnels, Aeronaut J, 1997, 101, (1010), pp 481–485.CrossRefGoogle Scholar
23.Kiya, M., Sasaki, K. and Arie, M.Discrete-vortex simulation of a turbulent separation bubble, J Fluid Mechanics, 1982, 120, pp 219–244.CrossRefGoogle Scholar
24.Lindgren, B. and Johansson, A.V.Evaluation of a new wind tunnel with expanding corners, Experiments in fuids, 2004, 36, (1), pp 197–203.Google Scholar
25.Na, Y. and Moin, P.Direct numerical simulation of a separated turbulent boundary layer, J Fluid Mechanics, 1998, 374, pp 379–405.CrossRefGoogle Scholar
26.Bradshaw, P.The effect of wind tunnel screens on nominally two-dimensional boundary layers, J Fluid Mechanics, 1965, 22, (4), pp 679–687.CrossRefGoogle Scholar
27.Bradshaw, P and Hellens, G.E. The N.P.L 59in × 9in Boundary-Layer Wind Tunnel, 1966, Aeronautical Research Council, Rep and Mem.Google Scholar
28.Perry, A.E. and Fairlie, B.D.A study of turbulent boundary-layer separation and reattachment, J Fluid Mechanics, 1975, 69, (4), pp 657–672.CrossRefGoogle Scholar
29.Metha, R.D.The aerodynamic design of blower windtunnels with wide angle diffusers, Prog Aero Sci, 1977, 18, pp 59–120.Google Scholar
30.Metha, R.D. and Bradshaw, P.Design rules for small low-speed windtunnels, Aeronaut J, 1979, 83, pp 443–449.Google Scholar
31.Rao, D.M. and Kariya, T.T. The Design and Preliminary Calibration of a Boundary-Layer Flow Channel. Technical report, 178399, NASA Contractor Report, 1987.Google Scholar
32.Ruderich, R. and Fernholz, H.H.An experimental investigation of a turbulent shear flow with separation, reverse flow, and reattachment, J Fluid Mechanics, 1986, 163, (1), pp 283–322.CrossRefGoogle Scholar
33Mokhtari, S. and Bradshaw, P.Longitudinal vortices in wind tunnel wall boundary layers, Aeronaut J, 1983, pp 233–236.CrossRefGoogle Scholar
34.Sarma, G.R. and Comte-Bellot, G.Automated constant voltage anemometer for measurements with fluid temperature drifts, Review of scientifc instruments, 2002, 73, (3), pp 1313–1317.CrossRefGoogle Scholar
35.Schwaab, Q. and Weiss, J.Evaluation of a thermal-tuft probe for turbulent separating and reattaching flows, ASME J Fluids Engineering, 137, 011401, 2015.CrossRefGoogle Scholar
36.Simpson, R.L.Aspects of turbulent boundary-layer separation, Progress in Aerospace Sciences, 1996, 32, pp 457–521.CrossRefGoogle Scholar
37.Smits, A.J., McKeon, B.J. and Marusic, I.High-Reynolds number Wall turbulence, Annual Review of Fluid Mechanics, 2011, 43, pp 353–375.CrossRefGoogle Scholar
38.Morel, T.Design of two-dimensional wind tunnel contractions, J Fluids Engineering, 1977, pp 371–378.CrossRefGoogle Scholar
39.Tavoularis, S.Measurements in Fluid Mechanics, Cambridge, 1st ed, 2005.Google Scholar
40.Patrick, W.P. Flowfield Measurements in a Separated and Reattached Flat Plate Turbulent Boundary Layer. Technical report, NASA Contractor Report 4052, 1987.Google Scholar
41.Weiss, J. and Comte-Bellot, G.Electronic noise in a constant voltage anemometer, Review of Scientific Instruments, 2004, 75, (5), pp 1290–1296.CrossRefGoogle Scholar
42.Wilcox, D.C.Turbulence modeling for CFD, 3, DCW industries La Cañada, 2006.Google Scholar
43.Wood, D.H. and Westphal, R.V.Measurements of the free-stream fluctuations above a turbulent boundary layer, Physics of Fluids, 1988, 31, (10), pp 2834–2840.CrossRefGoogle Scholar