In order to study the aerodynamics of a slot jet impinging a concave wall, flow visualizations, velocity measurements by particle image velocimetry (PIV) (mean velocity fields and the Reynolds stresses) and mean pressure measurements were carried out. Among the studied parameters is the effect of the relative curvature of the wall, in particular the low curvature radius because of the presence of three semistable positions. It is the first time that this type of behavior is observed in fluid mechanics. Thus three flow modes are observed and their behaviors are described. These different behaviors modify considerably the impinging jet structure and the turbulence values. Finally, from the pressure measurements, we were able to determine a criterion that allows us to know the behavior of the jet.
Issue Section:
Technical Papers
Keywords:
jets,
external flows,
aerodynamics,
flow visualisation,
turbulence,
cooling,
blades,
turbines
1.
Gau
, C.
, and Chung
, C. M.
, 1991, “Surface Curvature Effect on Slot-Air-Jet Impingement Cooling Flow and Heat Transfer Process
,” J. Heat Transfer
0022-1481, 113
, pp. 858
–864
.2.
Cornaro
, C.
, Fleischer
, A. S.
, and Goldstein
, J. R.
, 1999, “Flow Visualization of a Round Jet Impinging on Cylindrical Surfaces
,” Exp. Therm. Fluid Sci.
0894-1777, 20
, pp. 66
–78
.3.
Hrycak
, P.
, 1981, “Heat Transfer from a Row of Impinging Jets to Concave Cylindrical Surfaces
,” J. Heat Transfer
0022-1481, 24
, pp. 407
–419
.4.
Brahma
, R. K.
, Padhy
, I.
, and Pradham
, B.
, 1990, “Prediction of Stagnation Point Heat Transfer for a Single Round Jet Impinging on a Concave Hemispherical Surface
,” Waerme- Stoffuebertrag.
0042-9929, 26
, pp. 41
–48
.5.
Lee
, D. H.
, Chung
, Y. S.
, and Won
, S. Y.
, 1999, “The Effect of Concave Surface Curvature on Heat Transfer from a Fully Developed Round Impinging Jet
,” J. Heat Transfer
0022-1481, 42
, pp. 2489
–2497
.6.
Hrycak
, P.
, 1982, “Heat Transfer and Flow Characteristics of Jets Impinging on a Concave Hemispherical Plate
,” 7th Int. Heat Transfer Conference Munich, pp. 357
–362
.7.
Choi
, M.
, Yoo
, H. S.
, Yang
, G.
, and Lee
, J. S.
, 2000, “Measurement of Impinging Jet Flow and Heat Transfer on a Semi-Circular Concave Surface
,” J. Heat Transfer
0022-1481, 43
, pp. 1811
–1822
.8.
Yang
, G.
, Choi
, M.
, and Lee
, J. S.
, 1999, “An Experimental Study of Slot Jet Impingement Cooling on Concave Surface: Effects of Nozzle Configuration and Curvature
,” J. Heat Transfer
0022-1481, 42
, pp. 2199
–2209
.9.
Metzger
, D. E.
, Yamashita
, T.
, and Jenkins
, C. W.
, 1969, “Impingement Cooling of Concave Surfaces with Lines of Circular Air Jets
,” J. Eng. Power
0022-0825, pp. 149
–158
.10.
Chupp
, R. E.
, Helms
, H. E.
, McFadden
, P. W.
, and Brown
, T. R.
, 1969, “Evaluation of Internal Heat Transfer Coefficients for Impingement-Cooled Turbine Airfoils
,” J. Aircr.
0021-8669, 6
, pp. 203
–208
.11.
Tabakoff
, W.
, and Clevenger
, W.
, 1972, “Gas Turbine Blade Heat Transfer Augmentation by Impingement of Air Jets Having Various Configurations
,” J. Eng. Power
0022-0825, pp. 51
–60
.12.
Thomann
, H.
, 1968, “Effect of Streamwise Wall Curvature on Heat Transfer in a Turbulent Boundary Layer
,” J. Fluid Mech.
0022-1120, 33
, pp. 283
–292
.13.
Gardon
, R.
, and Akfirat
, J. C.
, 1966, “Heat Transfer Characteristics of Impinging Two-Dimensional Air Jets
,” 0022-1481 pp. 101
–107
.14.
Kataoka
, K.
, Suguro
, M.
, Degawa
, H.
, Marul
, I.
, and Mihata
, I.
, 1987, “The Effect of Structure Renewal due to Large-Scale Eddies on Jet Impingement Heat Transfer
,” Int. J. Heat Mass Transfer
0017-9310, 30
, pp. 559
–567
.15.
Rajaratnan
, N.
, 1976, Turbulent Jet
, Elsevier Scientific Publishing Compagny
, New York.16.
Westerweel
, J.
, and Willert
, C.
, 1998, “Principles of PIV Techniques. Application of Particles Image Theory an Pratice
,” Course at DRL, Göttingen, Germany.17.
Keane
, R. D.
, and Adrian
, R. J.
, 1990, “Optimization of Particle Image Velocimeters. Part 1: Double Pulsed Systems
,” Meas. Sci. Technol.
0957-0233, 1
, pp. 1202
–1215
.Copyright © 2005
by American Society of Mechanical Engineers
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