Measurements from heated boundary layers along a concave-curved test wall subject to high (initially 8 percent) free-stream turbulence intensity and strong (K = (ν/U∞2 dU∞/dx, as high as 9 × 10−6) acceleration are presented and discussed. Conditions for the experiments were chosen to simulate those present on the downstream half of the pressure side of a gas turbine airfoil. Turbulence statistics, including the turbulent shear stress, the turbulent heat flux, and the turbulent Prandtl number are presented. The transition zone is of extended length in spite of the high free-stream turbulence level. Turbulence quantities are strongly suppressed below values in unaccelerated turbulent boundary layers. Turbulent transport quantities rise with the intermittency, as the boundary layer proceeds through transition. Octant analysis shows a similar eddy structure in the present flow as was observed in transitional flows under low free-stream turbulence conditions. To the authors’ knowledge, this is the first detailed documentation of a high-free-stream-turbulence boundary layer flow in such a strong acceleration field.

Issue Section:
Forced Convection
Keywords:
Flow Transition, Forced Convection, Turbulence
Topics:
Boundary layers, Flow (Dynamics), Turbulence
1.
Blair
M. F.
, (
1992
), “
Boundary-Layer Transition in Accelerating Flows With Intense Freestream Turbulence: Part 1—Disturbances Upstream of Transition Onset
,”
ASME Journal of Fluids Engineering
, Vol.
114
, pp.
313
–
321
.
2.
Hishida
M.
, and
Nagano
Y.
, (
1978
), “
Simultaneous Measurements of Velocity and Temperature in Nonisothermal Flows
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
100
, pp.
340
–
345
.
3.
Jones
W. P.
, and
Launder
B. E.
, (
1972
), “
Some Properties of Sink-Flow Turbulent Boundary Layers
,”
J. Fluid Mech.
, Vol.
56
, pp.
337
–
351
.
4.
Kim, J., and Simon, T. W., (1991), “Free-Stream Turbulence and Concave Curvature Effects on Heated Transitional Boundary Layer: Vol. I—Final Report,” NASA CR 187150.
5.
Mayle
R. E.
, (
1991
), “
The Role of Laminar-Turbulent Transition in Gas Turbine Engines
,”
ASME Journal of Turbomachinery
, Vol.
113
, pp.
509
–
537
.
6.
Rued
K.
, and
Wittig
S.
, (
1986
), “
Laminar and Transitional Boundary Layer Structures in Accelerating Flow With Heat Transfer
,”
ASME Journal of Turbomachinery
, Vol.
108
, pp.
116
–
123
.
7.
Russ
S. G.
, and
Simon
T. W.
, (
1991
), “
On the Rotating, Slanted, Hot-Wire Technique
,”
Exp. in Fluids
, Vol.
12
, pp.
76
–
80
.
8.
Sohn, K. H., and Reshotko, E., (1991), “Experimental Study of Boundary Layer Transition with Elevated Freestream Turbulence on a Heated Flat Plate,” NASA CR 187068.
9.
Volino, R. J., and Simon, T. W., (1994a) “Transfer Functions for Turbulence Spectra,” Unsteady Flows in Aeropropulsion, ASME AD-Vol. 40, pp. 147–155.
10.
Volino
R. J.
, and
Simon
T. W.
, (
1994
b), “
An Application of Octant Analysis to Turbulent and Transitional Flow Data
,”
ASME Journal of Turbomachinery
, Vol.
116
, pp.
752
–
758
.
11.
Volino
R. J.
, and
Simon
T. W.
, (
1995
a), “
Bypass Transition in Boundary Layers Including Curvature and Favorable Pressure Gradient Effects
,”
ASME Journal of Turbomachinery
, Vol.
117
, pp.
166
–
174
.
12.
Volino, R. J., and Simon, T. W., (1995b), “Measurements in Transitional Boundary Layers under High Free-Stream Turbulence and Strong Acceleration Conditions,” NASA CR 198413.
13.
Volino
R. J.
, and
Simon
T. W.
, (
1997
), “
Boundary Layer Transition Under High Free-Stream Turbulence and Strong Acceleration Conditions: Part 1—Mean Flow Results
,”
ASME JOURNAL OF HEAT TRANSFER
, Vol.
119
, pp.
420
–
426
.
14.
Willmarth
W. W.
, and
Lu
S. S.
, (
1972
), “
Structure of the Reynolds Stress Near the Wall
,” .
J. Fluid Mech.
, Vol.
55
, pp.
65
–
92
.
This content is only available via PDF.
Copyright © 1997
 by The American Society of Mechanical Engineers
You do not currently have access to this content.