Usually less axial spacing between the blade rows of an axial flow compressor is associated with improved efficiency. However, mass flow rate, pressure ratio, and efficiency all decreased as the axial spacing between the stator and rotor was reduced in a transonic compressor rig. Reductions as great as 3.3% in pressure ratio, and 1.3 points of efficiency were observed as axial spacing between the blade rows was decreased from far apart to close together. The number of blades in the stator blade-row also affected stage performance. Higher stator blade-row solidity led to larger changes in pressure ratio efficiency, and mass flow rate with axial spacing variation. Analysis of the experimental data suggests that the drop in performance is a result of increased loss production due to blade-row interactions. Losses in addition to mixing loss are present when the blade-rows are spaced closer together. The extra losses are associated with the upstream stator wakes and are most significant in the midspan region of the flow.

1.
Adamczyk, J. J., 1985, “Model Equation for Simulating Flows in Multistage Turbomachines,” ASME Paper 85-GT-226.
2.
Adamczyk
,
J. J.
,
2000
, “
Aerodynamic Analysis of Multistage Turbomachinery Flows in Support of Aerodynamic Design
,”
ASME J. Turbomach.
,
122
, pp.
189
217
.
3.
Gorrell
,
S. E.
,
Okiishi
,
T. H.
, and
Copenhaver
,
W. W.
,
2002
, “
Stator-Rotor Interactions in a Transonic Compressor—Part 2: Description of a Loss Producing Mechanism
,” ASME Paper GT-2002-30495,
ASME J. Turbomach.
125
(
2
), pp.
336
345
.
4.
Smith, L. H., 1970, “Casing Boundary Layers in Multistage Axial, Flow Compressors,” Flow Research in Blading, ed. L. S. Dzung, Elsevier Publishing Company, Amsterdam.
5.
Mikolajczak, A. A., 1976, “The Practical Importance of Unsteady Flow,” AGARD CP 177, Unsteady Flow Phenomena in Turbomachinery.
6.
Smith
,
L. H.
,
1966
, “
Wake Dispersion in Turbomachines
,”
ASME J. Basic Eng.
,
Series D
, No.
3
, pp.
688
690
.
7.
Smith
,
L. H.
,
1993
, “
Wake Ingestion Propulsion Benefit
,”
J. Propul. Power
,
9
(
1
), pp.
74
82
.
8.
Deregal, P., and Tan, C. S., 1996, “Impact of Rotor Wakes on Steady-State Axial Compressor Performance,” ASME Paper 96-GT-253.
9.
Adamczyk, J. J., 1996, “Wake Mixing in Axial Flow Compressors,” ASME Paper 96-GT-29.
10.
Van Zante
,
D. E.
,
Adamczyk
,
J. J.
,
Strazisar
,
A. J.
, and
Okiishi
,
T. H.
,
1997
, “
Wake Recovery Performance Benefit in a High-Speed Axial Compressor
,” ASME Paper 97-GT-535,
ASME J. Turbomach.
124
, pp.
275
284
.
11.
van de Wall
,
A. G.
,
Kadambi
,
J. R.
, and
Adamczyk
,
J. J.
,
2000
, “
A Transport Model for the Deterministic Stresses Associated With Turbomachinery Blade Row Interactions
,”
ASME J. Turbomach.
,
122
, pp.
593
603
.
12.
Ottavy
,
X.
,
Trebinjac
,
I.
, and
Vouillarmet
,
A.
,
2001
, “
Analysis of the Interrow Flow Field Within a Transonic Axial Compressor—Part 1: Experimental Investigation
,”
ASME J. Turbomach.
,
123
, pp.
49
56
.
13.
Ottavy
,
X.
,
Trebinjac
,
I.
, and
Vouillarmet
,
A.
,
2001
, “
Analysis of the Interrow Flow Field Within a Transonic Axial Compressor—Part 2: Unsteady Flow Analysis
,”
ASME J. Turbomach.
,
123
, pp.
57
63
.
14.
Sanders, A. J., and Fleeter, S., 1999, “Transonic Rotor-IGV Interactions,” Presented at the thirteenth International Symposium on Air Breathing Engines, Chattanooga, TN (ISABE 99-7029).
15.
Law, C. H., and Wennerstrom, A. J., 1989, “Two Axial Compressor Designs for a Stage Matching Investigation,” AFWAL-TR-89-2005.
16.
Creason, T., and Baghdadi, S., 1988, “Design and Test of a Low Aspect Ratio Fan Stage,” AIAA Paper, 88-2816.
17.
Gorrell
,
S. E.
,
Copenhaver
,
W. W.
, and
Chriss
,
R. M.
,
2001
, “
Upstream Wake Influences on the Measured Performance of a Transonic Compressor Stage
,”
J. Propul. Power
,
17
, pp.
43
48
.
18.
Gorrell, S. E., 2001, “An Experimental and Numerical Investigation of Stator-Rotor Interactions in a Transonic Compressor,” Ph.D. dissertation, Department of Mechanical Engineering, Iowa State University.
19.
Cherret
,
M. A.
, and
Bryce
,
J. D.
,
1992
, “
Unsteady Viscous Flow in a High-Speed Core Compressor
,”
ASME J. Turbomach.
,
120
, pp.
287
294
.
20.
Camp
,
T. R.
, and
Shin
,
H. W.
,
1995
, “
Turbulence Intensity and Length Scale Measurements in Multistage Compressors
,”
ASME J. Turbomach.
,
117
, pp.
38
46
.
21.
1990, Recommended Practices for Measurement of Gas Path Pressures and Temperatures for Performance Assessment of Aircraft Turbine Engines and Components, AGARD Conf. Proc., AGARD-AR-245, ed. H. I. H Saravanamuttoo, North Atlantic Treaty Organization.
22.
Chriss, R. M., Copenhaver, W. W., and Gorrell, S. E., 1999, “The Effects of Blade-Row Spacing on the Flow Capacity of a Transonic Rotor,” ASME Paper 99-GT-209.
23.
Brookfield, J. M., Waitz, I. A., and Sell, J., 1996, “Wake Decay: Effect of Freestream Swirl,” ASME Paper 96-GT-495.
24.
Raj
,
R.
, and
Lakshminarayana
,
B.
,
1973
, “
Characteristics of the Wake Behind a Cascade of Airfoils
,”
J. Fluid Mech.
,
61
, pp.
707
730
.
25.
Stauter
,
R. C.
,
Dring
,
R. P.
, and
Carta
,
F. O.
,
1991
, “
Temporally and Spatially Resolved Flow in a Two-Stage Axial Flow Compressor—Part 1: Experiment
,”
ASME J. Turbomach.
,
113
, pp.
219
226
.
26.
Cumpsty, N. A., 1989, Compressor Aerodynamics, Longman Scientific & Technical, England.
You do not currently have access to this content.