This study examines the effects of surface roughness on the streamwise development of a vortex created by an isolated circular jet injected at 45 deg pitch and 90 deg skew into a crossflow. The study is motivated by the typical surface conditions encountered on in-service turbine blades of gas-turbine engines. Detailed measurements of the velocity field have been performed with a miniature four-wire probe at the jet exit plane, in the oncoming cross-stream boundary layer, and in a series of planes that capture the streamwise development of the vortex in the crossflow boundary layer up to about 15 jet-discharge diameters downstream of the jet. The paper presents the effects of surface roughness on the structure of the dominant streamwise vortex created by the interaction of the inclined jet with the mainstream, and documents the changes in the location, streamwise rate of change of circulation, and streamwise rate of diffusion of this vortex. Through these results, the change in the effectiveness of the vortex in energizing the boundary layer in the presence of surface roughness can be quantified.
Issue Section:
Technical Papers
Topics:
Boundary layers,
Cross-flow,
Flow (Dynamics),
Surface roughness,
Vortices,
Vorticity,
Wire,
Probes
1.
Schubauer
, G. B.
, and Spangenburg
, W. G.
, 1960
, “Forced Mixing in Boundary Layers
,” J. Fluid Mech.
, 8
, pp. 10
–31
.2.
Pearcey, H. H., 1961, “Shock Induced Separation and Its Prevention,” Boundary Layer and Flow Control, 2, Pergamon, New York, pp. 1170–1344.
3.
Spangler, J. G., and Wells, C. S., 1964, “Effects of Spiral Longitudinal Vortices on Turbulent Boundary Layer Skin friction,” NASA Contract Report 145.
4.
Shabaka
, I. M. M. A.
, Mehta
, R. D.
, and Bradshaw
, P.
, 1985
, “Longitudinal Vortices Embedded in Turbulent Boundary Layers, Part 1. Single Vortex
,” J. Fluid Mech.
, 155
, pp. 37
–57
.5.
Pearcey, H. H., Rao, K., and Sykes, D. M., 1993, “Inclined Jets Used as Vortex Generators to Suppress Shock-Induced Separation,” AGARD-CP-534, Computational and Experimental Assessment of Jets in Crossflow.
6.
McCormick, D. C., 1992, “Shock-Boundary Layer Interaction Control with Low Profile Vortex Generators and Passive Cavity,” AIAA Paper No. 92-0064.
7.
Zhang
, X.
, and Collins
, M. W.
, 1993
, “Flow and Heat Transfer in a Turbulent Boundary Layer through Jets
,” AIAA J.
, 31
(9
), pp. 1590
–1599
.8.
Reichert, B. A., and Wendt, B. J., 1993, “An Experimental Investigation of S-Duct Flow Control Using Arrays of Low Profile Vortex Generators,” AIAA Paper No. 93-0018.
9.
Anderson
, B. H.
, and Gibb
, J.
, 1998
, “Vortex-Generator Installation Studies on Steady-State and Dynamic Installation
,” J. Aircr.
, 35
, pp. 513
–520
.10.
Wendt, B. J., and Hingst, W. R., 1994, “Measurements and Modeling of Flow Structure in the Wake of a Low Profile Wishbone Vortex Generator,” AIAA Paper No. 94-0620.
11.
Rao, D. M., and Kariya, T. T., 1988, “Boundary-Layer Submerged Vortex Generators for Separation Control-An Exploratory Study,” AIAA Paper No. 883546-CP.
12.
Ashill, P. R., Fulker, J. L., and Hackett, K. C., 2002, “Studies of Flows Induced by Sub Boundary Layer Vortex Generator,” AIAA Paper No. 2002-0968.
13.
Wallis, R. A., 1952, “The Use of Air Jets for Boundary Layer Control,” Aerodynamics Research Labs, Aero. Note 110 (N-34736), Melbourne Australia.
14.
Compton
, D. A.
, and Johnston
, J. P.
, 1992
, “Streamwise Vortex Production by Pitched and Skewed Jets in a Turbulent Boundary Layer
,” AIAA J.
, 3
, No. 3
, pp. 640
–647
.15.
Selby
, G. V.
, Lin
, J. C.
, and Howard
, F. G.
, 1992
, “Control of Low-Speed Turbulent Separated Flow Using Jet Vortex Generators
,” Exp. Fluids
, 12
, No. 6
, pp. 394
–400
.16.
Zhang
, X.
, and Collins
, M. W.
, 1993
, “Flow and Heat Transfer in a Turbulent Boundary Layer Through Skewed and Pitched Jets
,” AIAA J.
, 31
, pp. 1590
–1599
.17.
Zhang
, X.
, and Collins
, M. W.
, 1997
, “Nearfield Evolution of a Longitudinal Vortex Generated by an Inclined Jet in a Turbulent Boundary Layer
,” ASME J. Fluids Eng.
, 119
, No. 4
, pp. 934
–939
.18.
Barberopoulos, A. A., and Garry, K. P., 1998, “The Effect of Skewing on the Vorticity Produced by an Airjet Vortex Generator,” paper no. 2275, Aeronaut. J., pp. 171–177.
19.
Findlay
, M. J.
, Salcudean
, M.
, and Gartshore
, I. S.
, 1999
, “Jets in Crossflow: Effects of Geometry and Blowing Ratio
,” ASME J. Fluids Eng.
, 121
, pp. 373
–378
.20.
Zhang
, X.
, 1998
, “Turbulence Measurements of a Longitudinal Vortex Generated by an Inclined Jet in a Turbulent Boundary Layer
,” ASME J. Fluids Eng.
, 120
, pp. 765
–771
.21.
Khan
, Z. U.
, and Johnston
, J. P.
, 2000
, “On Vortex Generating Jets
,” Int. J. Heat Fluid Flow
, 21
, pp. 506
–511
.22.
Johnston
, J. P.
, and Nishi
, M.
, 1990
, “Vortex Generator Jets—A Means for Flow Separation Control
,” AIAA J.
, 28
, No. 6
, pp. 989
–994
.23.
Wendt, B. J., and Reichert, B. A., 1996, “Spanwise Spacing Effects on the Initial Structure and Decay of Axial Vortices,” AIAA-96-2518-CP, pp. 1151–1161.
24.
Zhang
, X.
, 1999
, “Counter-Rotating Vortices Embedded in a Turbulent Boundary Layer with Inclined Jets
,” AIAA J.
, 37
, No. 10
, pp. 1277
–1284
.25.
Zhang, X., and Rona, A., 1999, “Measurements of Contra-Rotating Vortices in a Turbulent Boundary Layer,” AIAA Paper No. 99-0555.
26.
Johnston, J. P., 1999, “Pitched and Skewed Vortex-Generator Jets for Control of Turbulent Boundary Layer Separation: A Review,” Proceedings of the 3rd ASME/JSME Joint Fluids Engineering Conference, July 18–23, 1999, San Fransisco.
27.
Goldstein, R. J., and Jin, P., 2000, “Film Cooling Downstream of a Row of Discrete Holes with Compound Angle,” ASME Turbo Expo 2000, Paper No. 2000-GT-248, Munich, Germany.
28.
Zaman, K. B. M. Q., 1998, “Reduction of Jet Penetration in a Cross-Flow by using Tabs,” AIAA Paper No. 98-3276.
29.
Bons, J. P., Taylor, R. P., McClain, S. T., and Rivir, R. B., 2001, “The Many Faces of Turbine Surface Roughness,” ASME Turbo Expo 2001, Paper No. 2001-GT-0163, New Orleans, Louisiana.
30.
Dobbeling
, K.
, Lenze
, B.
, and Leuckel
, W.
, 1990
, “Computer-aided Calibration and Measurements with a Quadruple Hotwire Probe
,” Exp. Fluids
, 8
, pp. 257
–262
.31.
Lavoie
, P.
, and Pollard
, A.
, 2003
, “Uncertainty Analysis of Four-Sensor Hot-Wires and Their Data-Reduction Schemes in the Near Field of a Turbulent Jet
,” Exp. Fluids
, 34
, pp. 358
–370
.32.
Moffat
, R. J.
, 1982
, “Contributions to the Theory of Single-Sample Uncertainty Analysis
,” ASME J. Fluids Eng.
, 104
, pp. 250
–260
.33.
Bearman, P. W., 1971, “Corrections for the Effect of Ambient Temperature Drift on Hot-wire Measurements in Incompressible Flow,” DISA Information Report No. 11, pp. 25–30.
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