The aerodynamic performance of a turbine blade was evaluated via total pressure loss measurements on a linear cascade. The Reynolds number was varied from 600 000 to 1 200 000 to capture the operating regime for heavy-duty gas turbines. Four different types of surface roughness on the same profile were tested in the High Speed Cascade Wind Tunnel of the University of the German Armed Forces Munich and evaluated against a hydraulically smooth reference blade. The ratios of surface roughness to chord length for the test blade surfaces are in the range of Rac=7.6×1006-7.9×1005. The total pressure losses were evaluated from wake traverse measurements. The loss increase due to surface roughness was found to increase with increasing Reynolds number. For the maximum tested Reynolds number of Re=1200000 the increase in total pressure loss for the highest analysed surface roughness value of Ra=11.8μm was found to be 40% compared to a hydraulically smooth surface. The results of the measurements were compared to a correlation from literature as well as to well-documented measurements in literature. Good agreement was found for high Reynolds numbers between the correlation and the test results presented in this paper and the data available from literature.

1.
Lakshminarayana
,
B.
, 1996,
Fluid Dynamics and Heat Transfer of Turbomachinery
,
Wiley
, New York.
2.
Bons
,
J. P.
,
Taylor
,
R. P.
,
McClain
,
S. T.
and
Rivir
,
R. B.
, 2001, “
The Many Faces of Surface Roughness
,”
ASME J. Turbomach.
0889-504X,
123
, pp.
739
748
.
3.
Abuaf
,
N.
,
Bunker
,
R. S.
, and
Lee
,
C. P.
, “
Effects of Surface Roughness on Heat Transfer and Aerodynamic Performance of Turbine Airfoils
,” ASME-Paper No. 97-GT-10.
4.
Watt
,
R. M.
,
Allen
,
J. L.
,
Baines
,
N. C.
,
Simons
,
J. P.
, and
George
,
M.
, 1957, “
A Study of the Effects of Thermal Barrier Coating Surface Roughness on the Boundary Layer Characteristics of Gas-Turbine Aerofoils
,” ASME-Paper 87-GT-223.
5.
Boyle
,
R. J.
, and
Senyitko
,
R. G.
, “
Measurements and Predictions of Surface Roughness Effects on Turbine Vane Aerodynamics
,” ASME Paper GT2003-38580.
6.
Mayle
,
R. E.
, 1991,
”The Role of Laminar-Turbulent Transition in Gas Turbine Engines
,”
ASME J. Turbomach.
0889-504X,
113
, pp.
509
537
.
7.
Amecke
J.
, 1967,
Auswertung von Nachlaufmessungen an Ebenen Schaufelgittern
, Bericht 67 A49, AVA Göttingen.
8.
Amecke
,
J.
, and
Safarik
,
P.
, 1995, “
Data Reduction of Wake Flow Measurements with Injection of Other Gases
,” DLR Forschungsbericht 95-32, German Aerospace Center (DLR).
9.
Schlichting
,
H.
, and
Truckenbrodt
,
E.
, 1967,
Aerodynamik des Flugzeuges
, Vol.
1
,
2nd ed.
,
Springer-Verlag
, Berlin.
10.
Traupel
,
W.
, 1988,
Thermische Turbomaschinen
, Vol.
1
,
3rd ed.
,
Springer-Verlag
, Berlin.
11.
Prandtl
,
L.
, and
Schlichting
,
H.
, 1936, “
Das Widerstandsgesetz rauher Platten
,” Werft Reed, Hafen, pp.
1
4
;
also in “
Gesammelte Abandlungen
,” 1961,
Springer-Verlag
, Berlin, Vol.
2
, pp.
649
662
;
English translation in
Proc. Soc. Mech. Eng.
, U.S.A., 1936.
12.
Sturm
,
W.
, and
Fottner
,
L.
, 1985, “
The High-Speed Cascade Wind Tunnel of the German Armed Forces University Munich
,” Proceedings of the 8th Symposium on Measuring Techniques in Transonic and Supersonic Flow in Cascades and Turbomachines.
13.
Leipold
,
R.
, and
Fottner
,
L.
, 1998, “
A Measurement Technique to Investigate the Influence of Surface Roughness on the Flow Around a Highly Loaded Compressor Cascade
,”
14th Symposion on Measurement Techniques
, Limerick.
You do not currently have access to this content.