A boundary layer transition model is developed that accounts for the effects of periodic unsteady wake flow on the boundary layer transition. To establish the model, comprehensive unsteady boundary layer and heat transfer experimental investigations are conducted. The experiments are performed on a curved plate at zero-streamwise pressure gradient under periodic unsteady wake flow, where the frequency of the periodic unsteady flow is varied. The analysis of the time-dependent velocities, turbulence intensities, and turbulence intermittencies has identified three distinct quantities as primarily responsible for the transition of an unsteady boundary layer. These quantities, which exhibit the basis of the transition model presented in this paper, are: (1) relative intermittency, (2) maximum intermittency, and (3) minimum intermittency. To validate the developed transition model, it is implemented in an existing boundary layer code, and the resulting velocity profiles and the heat transfer coefficients are compared with the experimental data.

1.
Abu-Ghannam
B. J.
, and
Shaw
R.
,
1980
, “
Natural Transition of Boundary Layers—The Effects of Turbulence, Pressure Gradient and Flow History
,”
J. Mech. Eng. Sci.
, Vol.
22
, pp.
213
228
.
2.
Antonia, R. A., and Bradshaw, P., 1971, Imp. College Aero. Rep., No. 71-04.
3.
Bradshaw, P., and Murlis, J., 1973, Imp. College Aero. Tech. Note, No. 73-108.
4.
Crawford, M. E., and Kays, W. M., 1976, “STAN5 (TEXSTAN Version)—A Program for Numerical Computation of Two Dimensional Internal and External Boundary Layer Flow,” NASA CR-2742.
5.
Dhawan
S.
, and
Narasimha
R.
,
1958
, “
Some Properties of Boundary Layer Flow During the Transition From Laminar to Turbulent Motion
,”
Journal of Fluid Mechanics
, Vol.
3
, pp.
418
436
.
6.
Dullenkopf, K., and Mayle, R. E., 1994, ASME Paper N. 94-GT-174.
7.
Eifler, J., 1975, “Zur Frage der freien turbulenten Stro¨mungen, insbesondere hinter ruhenden und bewegten Zylindern,” Dissertation D-17, Technische Hochschule Darmstadt, Germany.
8.
Emmons
H. W.
,
1951
, “
The Laminar-Turbulent Transition in Boundary Layer—Part I
,”
J. Aero. Sci.
, Vol.
18
, pp.
490
498
.
9.
Gostelow
J. P.
, and
Blunden
A. R.
,
1989
, “
Investigations of Boundary Layer Transition in an Adverse Pressure Gradient
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
111
, pp.
366
375
.
10.
Gostelow
J. P.
,
Melwani
N.
, and
Walker
G. J.
,
1996
, “
Effects of Streamwise Pressure Gradient on Turbulent Spot Development
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
118
, pp.
737
743
.
11.
Gostelow, J. P., and Ramachandran, R. M., 1983, “Some Effects of Free Stream Turbulence on Boundary Layer Transition,” Proc. 8th Australasian Fluid Mechanics Conference.
1.
Halstead
E. D.
, et al.,
1997
, “
Boundary Layer Development in Axial Compressors and Turbines
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
119
, Part 1: pp.
114
127
;
2.
ASME JOURNAL OF TURBOMACHINERY
, Vol.
119
, Part 2: pp.
426
444
;
3.
ASME JOURNAL OF TURBOMACHINERY
, Vol.
119
, Part 3: pp.
225
237
;
4.
ASME JOURNAL OF TURBOMACHINERY
, Vol.
119
, Part 4: pp.
128
139
.
1.
Hedley
B. T.
, and
Keffer
F. J.
,
1974
, “
Turbulent/Non-Turbulent Decisions in an Intermittent Flow
,”
Journal of Fluid Mechanics
, Vol.
64
, pp.
625
644
.
2.
Herbst, R., 1980, “Entwicklung von Stro¨munggrenzsschichten bei instationa¨rer Zustro¨mung in Turbomaschinen,” Dissertation D-17, Technische Hochschule Darmstadt, Germany.
3.
Hippensteele
S. A.
,
Russell
L. M.
, and
Stepka
S.
,
1981
, “
Evaluation of a Method for Heat Transfer Measurements and Thermal Visualization Using a Composite of a Heater Element and Liquid Crystals
,”
ASME Journal of Heat Transfer
, Vol.
103
, pp.
184
189
.
4.
Hodson
H. P.
,
1990
, “
Modeling Unsteady Transition and Its Effects on Profile Loss
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
112
, pp.
691
701
.
5.
John
J.
, and
Schobeiri
M. T.
,
1996
, “
Development of Two-Dimensional Turbulent Wakes in a Curved Channel at Positive Streamwise Pressure Gradient
,”
ASME Journal of Fluids Engineering
, Vol.
118
, pp.
292
299
.
6.
Kovasznay
L. S. G.
,
Kibens
V.
, and
Blackwelder
R. F.
,
1970
,
J. Fluid Mech.
, Vol.
41
, pp.
283
283
.
7.
Launder, B. E., and Spalding, D. B., 1972, Mathematical Models of Turbulence, Academic Press, New York.
8.
Liu, X., and Rodi, W., 1992, “Measurement of Unsteady Flow and Heat Transfer in a Linear Turbine Cascade,” ASME Paper No. 92-GT-323.
9.
Mayle
R. E.
,
1991
, “
The Role of Laminar-Turbulent Transition in Gas Turbine Engines
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
113
, pp.
509
537
.
10.
Narasimha
R.
,
1957
, “
On the Distribution of Intermittency in the Transition Region of a Boundary Layer
,”
J. Aero. Sci.
, Vol.
24
, pp.
711
712
.
11.
Orth
U.
,
1993
, “
Unsteady Boundary-Layer Transition in Flow Periodically Disturbed by Wakes
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
115
, pp.
707
713
.
12.
Pache, W., 1976, “Zur Frage der Entwicklung von Stro¨mungsgrenzsschichten bei instationa¨rer Zustro¨mung in Turbomachinen,” Dissertation D-17, Technische Hochschule Darmstadt Germany.
13.
Patankar, S. V., and Spalding, D. B., 1970, Heat and Mass Transfer in Boundary Layers, 2nd ed., International Textbook Company Ltd., London.
14.
Paxson
D. E.
, and
Mayle
R. E.
,
1991
, “
Laminar Boundary Layer Interaction With an Unsteady Passing Wake
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
113
, pp.
419
427
.
15.
Pfeil, H., and Herbst, R., 1979, “Transition Procedure of Instationary Boundary Layers,” ASME Paper No. 79-GT-128.
16.
Pfeil
H.
,
Herbst
R.
, and
Schro¨der
T.
,
1983
, “
Investigation of the Laminar-Turbulent Transition of Boundary Layers Disturbed by Wakes
,”
ASME Journal of Engineering for Power
, Vol.
105
, pp.
130
137
.
17.
Schmidt
R. C.
, and
Patankar
S. V.
,
1991
, “
Simulating Boundary Layer Transition With Low-Reynolds-Number k–ε Turbulence Models: Part I—An Evaluation of Prediction Characteristics; Part II—An Approach to Improving the Predictions
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
113
, pp.
10
26
.
18.
Schobeiri, M. T., 1979, “Theoretische und experimentelle Untersuchungen laminarer und turbulenter Stro¨mungen in Diffusoren,” Dissertation D-17, Technische Hochschule Darmstadt, Germany.
19.
Schobeiri, M. T., and Radke, R., 1994, “Effects of Periodic Unsteady Wake Flow and Pressure Gradient on Boundary Layer Transition Along the Concave Surface of a Curved Plate,” ASME Paper No. 94-GT-327.
20.
Schobeiri, M. T., Read, K., and Lewalle, J., 1995a, “Effect of Unsteady Wake Passing Frequency on Boundary Layer Transition: Experimental Investigation and Wavelet Analysis,” ASME Paper No. 95-GT-437.
21.
Schobeiri
M. T.
,
Pappu
K.
, and
John
J.
,
1995
b, “
Theoretical and Experimental Study of Development of Two-Dimensional Steady and Unsteady Wakes Within Curved Channels
,”
ASME Journal of Fluids Engineering
, Vol.
117
, pp.
593
598
.
22.
Schobeiri
M. T.
,
John
J.
, and
Pappu
K.
,
1996
, “
Development of Two Dimensional Wakes Within Curved Channel: Theoretical Framework and Experimental Investigations
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
118
, pp.
506
518
.
23.
Walker, G. J., 1989, “Modeling of Transitional Flow in Laminar Separation Bubbles,” Proc. 9th Int. Symp. Air Breathing Engines, pp. 539–548.
24.
Wright, L., and Schobeiri, M. T., 1996, “Effect of Unsteady Wake Flow on Heat Transfer Along a Concave Surface,” to be submitted.
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