Labyrinth seals are widely used in industrial centrifugal compressors to reduce leakage. However, no work has been conducted to numerically investigate the detailed seal leakage flow and its effects in an environment of multistage centrifugal compressor. To clarify the flow mechanism of leakage flow and the interaction mechanism between leakage and mainstream flow in multistage centrifugal compressors, the flow of the last two stages from a four-stage centrifugal compressor is studied using computational fluid dynamics (CFD) model with and without considerations of labyrinth seal leakage paths, i.e., two shroud seals, one interstage seal, and one balance piston seal. The results show that the leakage flow in shroud and hub cavities can be described as a Batchelor-type flow. The Ekman number of the cavity Batchelor flow is small and corresponds to thin boundary layers while the Rossby number is at unity order implying the importance of rotating effects. The leakage flow through the shroud, interstage, and balance piston labyrinth seals is decreased by the combined effects of throttling and diffusion flow, and has distinctive flow structures associated with the type of labyrinth seal. The influence of leakage flow on the mainstream flow can be described by suction or injection mode. The suction mode is beneficial to the improvement of mainstream flow quality while the injection mode is harmful. This work is of scientific significance to enrich the knowledge of internal fluid mechanics and of potential application value to control and design the leakage flow in real configurations of multistage centrifugal compressors.

References

1.
Pinto
,
R. N.
,
Afzal
,
A.
,
D'Souza
,
L. V.
,
Ansari
,
Z.
, and
Samee
,
A. D. M.
,
2017
, “
Computational Fluid Dynamics in Turbomachinery: A Review of State of the Art
,”
Arch. Comput. Methods Eng.
,
24
(
3
), pp.
467
479
.
2.
Halawa
,
T.
,
Gadala
,
M. S.
,
Alqaradawi
,
M.
, and
Badr
,
O.
,
2016
, “
Influence of Changing Casing Groove Parameters on the Performance of Centrifugal Compressors Near Stall Condition
,”
ASME J. Fluids Eng.
,
138
(
2
), p.
021104
.
3.
Chen
,
H.
,
2017
, “
Component Matching of Centrifugal Compressors for Turbocharger Application
,”
ASME
Paper No. GT 2017-63108.
4.
Stuart
,
C.
,
Spence
,
S.
,
Filsinger
,
D.
,
Starke
,
A.
, and
Kim
,
S. I.
,
2018
, “
Characterizing the Influence of Impeller Exit Recirculation on Centrifugal Compressor Work Input
,”
ASME J. Turbomach.
,
140
(
1
), p.
011005
.
5.
Moore
,
J. J.
,
2003
, “
Three-Dimensional CFD Rotordynamic Analysis of Gas Labyrinth Seals
,”
ASME J. Vib. Acoust.
,
125
(
4
), pp.
427
433
.
6.
Hirano
,
T.
,
Guo
,
Z.
, and
Kirk
,
R. G.
,
2005
, “
Application of Computational Fluid Dynamics Analysis for Rotating Machinery—Part II: Labyrinth Seal Analysis
,”
ASME J. Eng. Gas Turbines Power
,
127
(
4
), pp.
820
826
.
7.
Eldin
,
A. M. G.
,
2007
, “
Leakage and Rotordynamic Effects of Pocket Damper Seals and See-Through Labyrinth Seals
,”
Ph.D. thesis
, Texas A&M University, College Station, TX.http://oaktrust.library.tamu.edu/handle/1969.1/ETD-TAMU-2084?show=full
8.
Li
,
Z. G.
,
Li
,
J.
, and
Feng
,
Z. P.
,
2016
, “
Labyrinth Seal Rotordynamic Characteristics—Part II: Geometrical Parameter Effects
,”
AIAA J. Propul. Power
,
32
(
5
), pp.
1281
1291
.
9.
Cangioli
,
F.
,
Pennacchi
,
P.
,
Vannini
,
G.
,
Ciuchicchi
,
L.
,
Vania
,
A.
,
Chatterton
,
S.
, and
Dang
,
P. V.
,
2017
, “
On the Thermodynamic Process in the Bulk-Flow Model for the Estimation of the Dynamic Coefficients of Labyrinth Seals
,”
ASME J. Eng. Gas Turbines Power
,
140
(
3
), p.
032502
.
10.
Guidotti
,
E.
,
Naldi
,
G.
,
Tapinassi
,
L.
, and
Chockalingam
,
V.
,
2012
, “
Cavity Flow Modeling in an Industrial Centrifugal Compressor Stage at Design and Off-Design Conditions
,”
ASME
Paper No. GT 2012-68288.
11.
Satish
,
K. V. V. N. K.
,
Guidotti
,
E.
,
Rubino
,
D. T.
,
Tapinassi
,
L.
, and
Prasad
,
S.
,
2013
, “
Accuracy of Centrifugal Compressor Stages Performance Prediction by Means of High Fidelity CFD and Validation Using Advanced Aerodynamic Probe
,”
ASME
Paper No. GT 2013-95618.
12.
Hildebrandt
,
A.
, and
Schilling
,
F.
,
2017
, “
Numerical and Experimental Investigation of Return Channel Vane Aerodynamics With Two-Dimensional and Three-Dimensional Vanes
,”
ASME J. Turbomach.
,
139
(
1
), p.
011010
.
13.
Mischo
,
B.
,
Ribi
,
B.
,
Seebass-Linggi
,
C.
, and
Mauri
,
S.
,
2009
, “
Influence of Labyrinth Seal Leakage on Centrifugal Compressor Performance
,”
ASME
Paper No. GT2009-59524.
14.
Weber
,
A.
,
Morsbach
,
C.
,
Kügeler
,
E.
,
Rube
,
C.
, and
Wedeking
,
M.
,
2016
, “
Flow Analysis of a High Flow Rate Centrifugal Compressor Stage and Comparison With Test Rig Data
,”
ASME
Paper No. GT2016-56551.
15.
Sun
,
Z. G.
,
Tan
,
C. Q.
, and
Zhang
,
D. Y.
,
2009
, “
Flow Field Structures of the Impeller Backside Cavity and Its Influences on the Centrifugal Compressor
,”
ASME
Paper No. GT2009-59879.
16.
Kaluza
,
P.
,
Landgraf
,
C.
,
Schwarz
,
P.
,
Jeschke
,
P.
, and
Smythe
,
C.
,
2017
, “
On the Influence of a Hubside Exducer Cavity and Bleed Air in a Close-Coupled Centrifugal Compressor Stage
,”
ASME J. Turbomach.
,
139
(
7
), p.
071011
.
17.
Wang
,
Z. H.
, and
Xi
,
G.
,
2011
, “
Influences of Cavity Leakage on the Design of Low Flow Coefficient Centrifugal Impeller
,”
Sci. China Technol. Sci.
,
54
(
2
), pp.
311
317
.
18.
Marechale
,
R.
,
Ji
,
M.
, and
Cave
,
M.
,
2015
, “
Experimental and Numerical Investigation of Labyrinth Seal Clearance Impact on Centrifugal Impeller Performance
,”
ASME
Paper No. GT2015-43778
.
19.
Munk
,
D. J.
,
Kipouros
,
T.
,
Vio
,
G. A.
,
Parks
,
G. T.
, and
Steven
,
G. P.
,
2018
, “
Multiobjective and Multi-Physics Topology Optimization Using an Updated Smart Normal Constraint Bi-Directional Evolutionary Structural Optimization Method
,”
Struct. Multidiscip. Optim.
,
57
(
2
), pp.
665
688
.
20.
Yan
,
H.
,
Liu
,
Y. W.
,
Li
,
Q. S.
, and
Lu
,
L. P.
,
2018
, “
Turbulence Characteristics in Corner Separation in a Highly Loaded Linear Compressor Cascade
,”
Aerosp. Sci. Technol.
,
75
, pp.
139
154
.
21.
Serre
,
E.
,
Del Arco
,
E. C.
, and
Bontoux
,
P.
,
2001
, “
Annular and Spiral Patterns in Flows Between Rotating and Stationary Discs
,”
J. Fluid Mech.
,
434
, pp.
65
100
.
22.
Poncet
,
S.
,
Schiestel
,
R.
, and
Chauve
,
M. P.
,
2005
, “
Centrifugal Flow in a Rotor-Stator Cavity
,”
ASME J. Fluids Eng.
,
127
(
4
), pp.
787
794
.
23.
Liu
,
G.
,
Du
,
Q.
,
Liu
,
J.
,
Wang
,
P.
, and
Zhu
,
J. Q.
,
2016
, “
Numerical Investigation of Radial Inflow in the Impeller Rear Cavity With and Without Baffle
,”
Sci. China Technol. Sci.
,
59
(
3
), pp.
456
467
.
24.
Wang
,
C. Z.
,
Tang
,
F.
,
Li
,
Q.
, and
Wang
,
X. H.
,
2018
, “
Experimental Investigation of the Microscale Rotor–Stator Cavity Flow With Rotating Superhydrophobic Surface
,”
Exp. Fluids
,
59
(
3
), p.
47
.
25.
Batchelor
,
G. K.
,
1951
, “
Note on a Class of Solutions of the Navier-Stokes Equations Representing Steady Rotationally-Symmetric Flow
,”
Q. J. Mech. Appl. Math.
,
4
(
1
), pp.
29
41
.
26.
Bödewadt
,
U. T.
,
1940
, “
Die Drehströmung über festem Grunde
,”
Z. Angew. Math. Mech.
,
20
(
5
), pp.
241
253
.
27.
Ekman
,
V. W.
,
1905
, “
On the Influence of the Earth's Rotation on Ocean-Currents
,”
Ark. Mat. Astron. Fys.
,
2
(
11
), pp.
1
52
.https://jscholarship.library.jhu.edu/handle/1774.2/33989
28.
Childs
,
P. R. N.
,
2011
,
Rotating Flow
,
Butterworth-Heinemann
,
Oxford, UK
.
29.
Wang
,
B.
,
Okamoto
,
K.
,
Yamaguchi
,
K.
, and
Teramoto
,
S.
,
2014
, “
Loss Mechanisms in Shear-Force Pump With Multiple Corotating Disks
,”
ASME J. Fluids Eng.
,
136
(
8
), p.
081101
.
30.
Greitzer
,
E. M.
,
Tan
,
C. S.
, and
Graf
,
M. B.
,
2004
,
Internal Flow: Concepts and Applications
,
Cambridge University Press
,
New York
.
31.
Owen
,
J. M.
,
1989
, “
An Approximate Solution for the Flow Between a Rotating and a Stationary Disk
,”
ASME J. Turbomach.
,
111
(
3
), pp.
323
332
.
32.
Itoh
,
M.
,
Yamada
,
Y.
,
Imao
,
S.
, and
Gonda
,
M.
,
1992
, “
Experiments on Turbulent Flow Due to an Enclosed Rotating Disk
,”
Exp. Therm. Fluid Sci.
,
5
(
3
), pp.
359
368
.
33.
Debuchy
,
R.
,
Nour
,
F. A.
, and
Bois
,
G.
,
2010
, “
An Analytical Modeling of the Central Core Flow in a Rotor-Stator System With Several Preswirl Conditions
,”
ASME J. Fluids Eng.
,
132
(
6
), p.
061102
.
34.
Özkan
,
M.
,
Thomas
,
P. J.
,
Cooper
,
A. J.
, and
Garrett
,
S. J.
,
2017
, “
Comparison of the Effects of Surface Roughness and Confinement on Rotor–Stator Cavity Flow
,”
Eng. Appl. Comput. Fluid Mech.
,
11
(
1
), pp.
142
158
.
35.
Gantar
,
M.
,
Florjancic
,
D.
, and
Sirok
,
B.
,
2002
, “
Hydraulic Axial Thrust in Multistage Pumps—Origins and Solutions
,”
ASME J. Fluids Eng.
,
124
(
2
), pp.
336
341
.
36.
Gad-el-Hak
,
M.
, and
Bushnell
,
D. M.
,
1991
, “
Separation Control: Review
,”
ASME J. Fluids Eng.
,
113
(
1
), pp.
5
30
.
37.
Atik
,
H.
, and
van Dommelen
,
L.
,
2008
, “
Autogenous Suction to Prevent Laminar Boundary-Layer Separation
,”
ASME J. Fluids Eng.
,
130
(
1
), p.
011201
.
38.
Chinyoka
,
T.
,
2011
, “
Suction-Injection Control of Shear Banding in Non-Isothermal and Exothermic Channel Flow of Johnson-Segalman Liquids
,”
ASME J. Fluids Eng.
,
133
(
7
), p.
071205
.
39.
Keerthi
,
M. C.
,
Kushari
,
A.
, and
Somasundaram
,
V.
,
2017
, “
Experimental Study of Suction Flow Control Effectiveness in a Serpentine Intake
,”
ASME J. Fluids Eng.
,
139
(
10
), p.
101104
.
40.
Ju
,
Y. P.
,
Zhang
,
C. H.
, and
Chi
,
X. L.
,
2012
, “
Optimization of Centrifugal Impellers for Uniform Discharge Flow and Wide Operating Range
,”
AIAA J. Propul. Power
,
28
(
5
), pp.
888
899
.
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