The present paper deals with the numerical and experimental investigation of the effect of return channel (RCH) dimensions of a centrifugal compressor stage on the aerodynamic performance. Three different return channel stages were investigated, two stages comprising three-dimensional (3D) return channel blades and one stage comprising two-dimensional (2D) RCH vanes. The analysis was performed regarding both the investigation of overall performance (stage efficiency, RCH total pressure loss coefficient) and detailed flow-field performance. For detailed experimental flow-field investigation at the stage exit, six circumferentially traversed three-hole probes were positioned downstream the return channel exit in order to get two-dimensional flow-field information. Additionally, static pressure wall measurements were taken at the hub and shroud pressure and suction side (SS) of the 2D and 3D return channel blades. The return channel system overall performance was calculated by measurements of the circumferentially averaged 1D flow field downstream the diffuser exit and downstream the stage exit. Dependent on the type of return channel blade, the numerical and experimental results show a significant effect on the flow field overall and detail performance. In general, satisfactory agreement between computational fluid dynamics (CFD)-prediction and test-rig measurements was achieved regarding overall and flow-field performance. In comparison with the measurements, the CFD-calculated stage performance (efficiency and pressure rise coefficient) of all the 3D-RCH stages was slightly overpredicted. Very good agreement between CFD and measurement results was found for the static pressure distribution on the RCH wall surfaces while small CFD-deviations occur in the measured flow angle at the stage exit, dependent on the turbulence model selected.

References

References
1.
Lenke
,
L. J.
, and
Simon
,
H.
,
1998
, “
Numerical Investigations Within Return Channels of Multi-Stage Centrifugal Compressors
,” VDI-Berichte Nr. 1425.
2.
Lenke
,
L. J.
, and
Simon
,
H.
,
1999
, “
Numerical Investigations on the Optimum Design of Return Channels of Multi-Stage Centrifugal Compressors
,”
ASME
Paper No. 99-GT-103.
3.
Fister
,
W.
,
Zahn
,
G.
, and
Tasche
,
J.
,
1982
, “
Theoretical and Experimental Investigations About Vaneless Return Channels of Multi-Stage Radial Flow Turbomachines
,”
ASME
Paper No. 82-GT-209.
4.
Inoue
,
Y.
, and
Koizumi
,
T.
,
1983
, “
An Experimental Study on Flow Patterns and Losses in Return Passages for Centrifugal Compressors
,” ASME Conference for Applied Mechanics, Bioengineering and Fluids Engienering, Houston, TX, Vol. 3, pp.
13
21
.
5.
Rothstein
,
E.
,
1984
, “
Experimentelle und Theoretische Untersuchung der Stromungsvorgange in Ruckfuhrkanalen von Radialverdichterstufen, insbesondere solcher mit geringen Kanalbreiten
,” Dissertation, RWTH-Aachen, Aachen, Germany.
6.
Nishida
,
Y.
,
Kobayashi
,
H.
,
Nishida
,
H.
, and
Sugimura
,
K.
,
2013
, “
Performance Improvement of a Return Channel in a Multistage Centrifugal Compressor Using Multiobjective Optimization
,”
ASME J. Turbomach.
,
135
(
3
), p.
031026
.
7.
Aalburg
,
C.
,
Simpson
,
A.
,
Carretero
,
J.
,
Nguyen
,
T.
, and
Michelassi
,
V.
,
2009
, “
Extension of the Stator Vane Upstream Across the 180deg Bend for a Multi-Stage Radial Compressor Stage
,”
ASME
Paper No. GT2009-59522.
8.
Aalburg
,
C.
,
Sezal
,
I.
,
Haigermoser
,
C.
,
Simpson
,
A.
,
Michelassi
,
V.
, and
Sassanelli
,
G.
,
2011
, “
Annular Cascade for Radial Compressor Development
,”
ASME
Paper No. GT2011-46834.
9.
Toyokura
,
T.
,
Kanemoto
,
T.
, and
Hatta
,
M.
,
1986
, “
Studies on Circular Cascades for Return Channels of Centrifugal Turbomachinery (1st Report, Inverse Method and Cascade Design)
,”
Bull. JSME
,
29
(
255
), pp.
2885
2892
.
10.
De Bellis
,
F.
,
Guidotti
,
E.
, and
Rubino
,
D. T.
,
2015
, “
Centrifugal Compressors Return Channel Optimization by Means of Advanced 3D CFD
,”
ASME
Paper No. GT2015-44143.
11.
Reutter
,
O.
,
Hildebrandt
,
A.
,
Jakiel
,
C.
,
Raitor
,
T.
, and
Voss
,
C.
,
2011
, “
Automated Aerodynamic Optimization of a Return Channel Vane of a Multi-Stage Radial Compressor
,”
9th European Turbomachinery Conference
, Istanbul, Turkey, Mar. 21–25, pp.
1507
1516
.
12.
Hildebrandt
,
A.
,
2012
, “
Numerical Analysis of Overall Performance and Flow Phenomena of an Automatically Optimized Three-Dimensional Return Channel System for Multistage Centrifugal Compression Systems
,”
ASME
Paper No. GT2012-68559.
13.
Veress
,
A.
, and
Van den Braembussche
,
R.
,
2004
, “
Inverse Design and Optimization of a Return Channel for a Multi-Stage Centrifugal Compressor
,”
ASME J. Fluids Eng.
,
126
(
5
), pp.
799
806
.
14.
Verstraete
,
T.
,
Hildebrandt
,
A.
, and
Van den Braembussche
,
R.
,
2011
, “
Multidisciplinary Design and Off-Design Optimization of a Radial Compressor for Industrial Applications
,”
10th International Symposium on Experimental Computational Aerothermodynamics of Internal Flows
, July 4–7, Brussels, Belgium, July 4–7, Paper No. ISAIF10-153.
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