Analysis of multistage compressor stator surface static pressure data reveals that the radial growth of suction surface corner separation prematurely separates core flow stator sections, limiting their pressure rise capability and generating endwall loss. Modeling of the stator flowfield, using a three-dimensional Euler analysis, has led to the development of “bowed” stator shapes, which generate radial forces that reduce diffusion rates in the suction surface corners, in order to delay the onset of corner separation. Experimental testing of the bowed stator concept in a three-stage research compressor has confirmed the elimination of suction surface corner separation, the resulting reduction of the endwall loss, and the increase in pressure rise capability of the stator core sections. This results in more robust pressure rise characteristics and substantially improved efficiency over the entire flow range of the compressor. The strong interaction effects of the bowed stator with the viscous endwall flowfield are shown to be predictable using a three-dimensional multistage Navier–Stokes analysis. This permits matching of the rotors to the altered stator exit profiles, in order to avoid potential stability limiting interactions. Application of bowed stators to a high bypass ratio engine eleven-stage high-pressure compressor has resulted in substantial improvement in efficiency, with no stability penalty.

1.
Behlke
R. F.
,
1986
, “
The Development of a Second-Generation of Controlled Diffusion Airfoils for Multistage Compressors
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
108
, pp.
32
40
.
2.
Breugelmans
F. A. H.
,
Carels
Y.
, and
Demuth
M.
,
1984
, “
Influence of Dihedral on the Secondary Flow in a Two-Dimensional Compressor Cascade
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
106
, pp.
578
584
.
3.
Cyrus, V., 1986, “Experimental Study of Three-Dimensional Flow in an Axial Compressor Stage,” ASME Paper No. 86-GT-118.
4.
Dunham, J., 1972, “Prediction of Boundary Layer Transition on Turbomachinery Blades,” AGARD-AG-164.
5.
Hobbs
D. E.
, and
Weingold
H. D.
,
1984
, “
Development of Controlled Diffusion Airfoils for Multistage Compressor Application
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
106
, pp.
271
278
.
6.
Joslyn
H. D.
, and
Dring
R. P.
,
1985
, “
Axial Compressor Stator Aerodynamics
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
107
, pp.
485
493
.
7.
LeJambre, C. R., Zacharias, R. M., Biederman, B. P., Gleixner, A. J., and Yetka, C. J., 1995, “Development and Application of a Multistage Navier-Stokes Solver, Part II: Application to a High Pressure Compressor Design,” ASME Paper No. 95-GT-343; accepted for publication in the JOURNAL OF TURBOMACHINERY.
8.
McNally, W. D., 1970, “Fortran Program for Calculating Compressible Laminar and Turbulent Boundary Layers in Arbitrary pressure Gradients,” NASA TN D-5681.
9.
Ni, R.-H., 1981, “A Multiple Grid Scheme for Solving Euler Equations,” AIAA Paper No. 81-1025.
10.
Peacock, R. E., 1967, “Flow Control in the Corners of Cascades,” Aeronautical Research Council Report ARC 27, 291 P.A. 1121.
11.
Rhie, C. M., 1986, “A Pressure Based Navier-Stokes Solver Using the Multigrid Method,” AIAA Paper No. 86-0207.
12.
Rhie, C. M., Gleixner, A. J., Spear, D. A., Fischberg, C. J., and Zacharias, R. M., 1995, “Development and Application of a Multistage Navier-Stokes Solver, Part I: Multistage Modeling Using Body-forces and Deterministic Stresses,” ASME Paper No. 95-GT-342; accepted for publication with ASME JOURNAL OF TURBOMACHINERY.
13.
Roberts, W. B., 1979, “Calculation of Laminar Separation Bubbles and Their Effect on Airfoil Performance,” AIAA Paper No. 79-0285.
14.
Robinson, C. J., Northall, J. D., and McFarlane, C. W. R., 1989, “Measurement and Calculation of the Three-Dimensional Flow in Axial Compressor Stators, With and Without Endbends,” ASME Paper No. 89-GT-6.
15.
Schulz
H. D.
,
Gallus
H. E.
, and
Lakshminarayana
B.
,
1990
, “
Three Dimensional Separated Flow Field in the Endwall Region of an Annular Compressor Cascade in the Presence of Rotor–Stator Interaction: Part I—Quasi-Steady Flow Field and Comparison With Steady State Data
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
112
, pp.
669
678
.
16.
Shang, E., Wang, Z. Q., and Su, J. X., 1993, “The Experimental Investigations on the Compressor Cascades With Leaned and Curved Blades,” ASME Paper No. 93-GT-50.
17.
Stewart, W. L., 1955, “Analysis of Two-Dimensional Compressible Flow Loss Characteristics Downstream of Turbomachine Blade Rows in Terms of Basic Boundary Layer Characteristics,” NACA TN 3515.
18.
Sturm
W.
,
Scheugenpflug
H.
, and
Fottner
L.
,
1992
, “
Performance Improvements of Compressor Cascades by Controlling the Profile and Sidewall Boundary Layers
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
114
, pp.
477
486
.
19.
Tang, Y.-P., and Chen, M.-Z., 1988, “An Experimental Investigation of a Vortex Flow Cascade,” ASME Paper No. 88-GT-265.
20.
Tweedt
D. L.
,
Okiishi
T. N.
, and
Hathaway
M. D.
,
1986
, “
Stator Endwall Sweep and Hub Shroud Influence on Compressor Performance
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
108
, pp.
224
232
.
21.
Wang, Z. Q., Su, J. X., and Zhong, J., 1994, “The Effect of the Pressure Distribution in a Three-Dimensional Flow Field of a Cascade on the Type of Curved Blades,” ASME Paper No. 94-GT-409.
22.
Weingold
H. D.
, and
Behlke
R. F.
,
1987
, “
The Use of Surface Static Pressure Data as a Diagnostic Tool in Multistage Compressor Development
,”
ASME JOURNAL OF TURBOMACHINERY
, Vol.
109
, pp.
123
129
.
23.
Weingold, H. D., Neubert, R. J., Andy, J. G., Behlke, R. F., and Potter, G. E., 1992, United States Patent 5,088,892, “Bowed Airfoil for the Compression Section of a Rotary Machine,”
24.
Wisler
D. C.
,
1985
, “
Loss Reduction in Axial-Flow Compressors Through Low-Speed Model Testing
,”
ASME Journal of Engineering for Gas Turbines and Power
, Vol.
107
, pp.
354
363
.
This content is only available via PDF.
You do not currently have access to this content.