In this study, experiments and numerical simulations were carried out to evaluate the effects of radially distorted incident flow on the performance of axial-flow fans, which were equipped with three kinds of forward-skewed blades. Loss coefficient and velocity components at exit section as well as overall performance are discussed, both at the design point and the lower mass flow rate point. Furthermore, rotating stall was also observed by use of three dynamic pressure sensors. All results reveal that there are beneficial effects of forward-skewed blades on the fan performance, but the fan performance and its unsteady aerodynamic characteristics are quite affected by the radially distorted incident flow.

References

1.
Harry
III,
D. P.
, and
Lubick
,
R. J.
,
1955
, “
Inlet-Air Distortion Effects on Stall, Surge, and Acceleration Margin of a Turbojet Engine Equipped With Variable Compressor Inlet Guide Vanes
,”
NACA RM E54K26
.
2.
Sandercock
,
D. M.
, and
Sanger
,
N. L.
,
1974
, “
Some Observations of the Effects of Radial Distortions on Performance of a Transonic Rotating Blade Row
,”
NASA TN D-7842
.
3.
Spakovszky
,
Z. S.
,
Weigl
,
H. J.
,
Paduano
,
J. D.
,
van Schalkwyk
,
C. M.
,
Suder
,
K. L.
, and
Bright
,
M. M.
,
1999
, “
Rotating Stall Control in a High-Speed Stage With Inlet Distortion: Part I—Radial Distortion
,”
ASME J. Turbomach.
,
121
,
pp.
510
516
.10.1115/1.2841345
4.
Leinhos
,
D. C.
,
Schmid
,
N. R.
, and
Fottner
,
L.
,
2001
, “
The Influence of Transient Inlet Distortion on the Instability Inception of a Low-Pressure Compressor in a Turbofan Engine
,”
ASME J. Turbomach.
,
123
,
pp.
1
8
.10.1115/1.1330271
5.
Chima
,
R. V.
,
2006
, “
A Three-Dimensional Unsteady CFD Model of Compressor Stability
,”
NASA TM-2006-214117
.
6.
Hah
,
C.
,
Rabe
,
D. C.
,
Sullivan
,
T. J.
, and
Wadia
,
A. R.
,
1998
, “
Effect of Inlet Distortion on the Flow Field in a Transonic Compressor Rotor
,”
ASME J. Turbomach.
,
120
,
pp.
233
246
.10.1115/1.2841398
7.
Salta
,
C. A.
, and
Kroger
,
D. G.
,
1995
, “
Effect of Inlet Flow Distortion on Fan Performance in Forced Draught Air-Cooled Heat Exchangers
,”
Heat Recovery Systems and CHP
,
15
(
6
),
pp.
555
561
.10.1016/0890-4332(95)90065-9
8.
Jang
,
Ch.
,
Choi
,
S.
, and
Kim
,
K.
,
2008
, “
Effects of Inflow Distortion Due to Hub Cap's Shape on the Performance of Axial Flow Fan
,”
J. Fluid Sci. Tech.
,
3
(
5
),
pp.
598
609
.10.1299/jfst.3.598
9.
Smith
,
L. H.
, and
Yeh
,
H.
,
1963
, “
Sweep and Dihedral Effects in Axial-Flow Turbomachinery
,”
ASME J. Basic Eng.
,
85
(
2
),
pp.
401
416
.10.1115/1.3656623
10.
Gallimore
,
S. J.
,
Bolger
,
J. J.
,
Cumpsty
,
N. A.
,
Taylor
,
M. J.
,
Wright
,
P. I.
, and
Place
,
J. M. M.
,
2002
, “
The Use of Sweep and Dihedral in Multistage Axial Flow Compressor Blading—Parts I and II
,”
ASME J. Turbomach.
,
124
,
pp.
521
531
.10.1115/1.1507333
11.
Carolus
,
T. H.
, and
Beiler
,
M. G.
,
1997
, “
Skewed Blade in Low Pressure Fans: A Survey of Noise Reduction Mechanism
,”
AIAA Paper No. 97-1591-CP
.
12.
Beiler
,
M. G.
, and
Carolus
,
T. H.
,
1986
, “
Computation and Measurement of the Flow in Axial Flow Fans With Skewed Blades
,”
ASME J. Turbomach.
,
121
,
pp.
59
66
.10.1115/1.2841234
13.
Breugelmans
,
F. A. E.
,
Carels
,
Y.
, and
Demuth
,
M.
,
1984
, “
Influence of Dihedral on the Secondary Flow in a Two Dimensional Compressor Cascade
,”
ASME J. Eng. Gas Turb. Power
,
106
(
3
),
pp.
578
584
.10.1115/1.3239609
14.
Sasaki
,
T.
, and
Breugelmans
,
F. A. E.
,
1997
, “
Comparison of Sweep and Dihedral Effects on Compressor Cascade Performance
,”
ASME Paper No. 97-GT-2
.
15.
Chinese Technical Committee of Compressor and Blower
,
2000
,
Test Methods of Aerodynamic Performance for Fans
,
Standards Press of China
,
Beijing, China
.
16.
NUMECA Intl.
,
2000
,
Numeca's Flow Integrated Environment for Turbomachinery and Internal Flows, User Manual
,
NUMECA Intl.
,
Brussels, Belgium
.
17.
Wilcox
,
D. C.
,
1993
, “
Comparison of Two-Equation Turbulence Models for Boundary Layers with Pressure Gradient
,”
AIAA J.
,
23
,
pp.
1414
1421
.10.2514/3.11790
18.
Menter
,
F. R.
,
1992
, “
Performance of Popular Turbulence Models for Attached and Separated Adverse Pressure Gradient Flows
,”
AIAA J.
,
30
(
8
),
pp.
2066
2072
.10.2514/3.11180
19.
Yang
,
B.
,
2001
, “
A New Blade Design Scheme for Reversible Axial Flow Fan & Research on the Combined Cascades
,”
Doctoral dissertation
,
Shanghai Jiaotong University
,
Shanghai, China
.
20.
Yamaguchi
,
N.
,
Tominaga
,
T.
,
Masutani
,
J.
, and
Goto
,
M.
,
1993
, “
Performance Improvement by Forward-Skewed Blading of Axial-Fan Moving Blades
,”
Proceedings of the 11th International Symposium on Air Breathing Engines (ISABE ’93), Tokyo, September 20–24, Paper No. ISABE 93-7055, pp.
580
589
.
21.
Govardhan
,
M.
,
Kumar
,
O. G. K.
, and
Sittaram
,
N.
,
2007
, “
Investigation on Low Speed Axial Compressor With Forward and Backward Sweep
,”
J. Therm. Sci.
,
16
(
2
),
pp.
121
123
.10.1007/s11630-007-0121-3
22.
Gu
,
C. G.
, and
Yang
,
B.
,
2008
, “
Optimum Design of Axial Flow Fan
,”
Key Lab. for Power Machinery & Engineering of Ministry of Education Shanghai Jiaotong University Technical Report
.
You do not currently have access to this content.