This paper presents an investigation of the effects of ported shroud (PS) self-recirculating casing treatment used in turbocharger centrifugal compressors for increasing the operable range. The investigation consists of computing three-dimensional flow in a representative centrifugal compressor with and without PS at various levels of approximations in flow physics and geometrical configuration; this provides an enabler for establishing the causal link between PS flow effects and compressor performance changes. It is shown that the main flow path perceives the PS flow as a combination of flow actuations that include injection and removal of mass flow and injection of axial momentum and tangential momentum. A computational model in which the presence of the PS is replaced by imposed boundary conditions (BCs) that reflect the individual flow actuations has thus been formulated and implemented. The removal of a fraction of the inducer mass flow has been determined to be the dominant flow actuation in setting the performance of PS compressors. Mass flow removal reduces the flow blockage associated with the impeller tip leakage flow and increases the diffusion in the main flow path. Adding swirl to the injected flow in the direction opposite to the wheel rotation results in an increase of the stagnation pressure ratio and a decrease of the efficiency. The loss generation in the flow path has been defined to rationalize efficiency changes associated with PS compressor operation.

References

References
1.
Fisher
,
F. B.
,
1988
, “
Application of Map Width Enhancement Devices to Turbocharger Compressor Stages
,”
SAE
Paper No. 880794.
2.
Uchida
,
H.
,
Kashimoto
,
A.
, and
Iwakiri
,
Y.
,
2006
, “
Development of Wide Flow Range Compressor With Variable Inlet Guide Vane
,”
R&D Rev. Toyota CRDL
,
41
(
3
), pp. 9–14.
3.
Iwakiri
,
Y.
, and
Uchida
,
H.
,
2006
, “
Numerical Fluid Analysis of a Variable Geometry Compressor for Use in a Turbocharger
,”
R&D Rev. Toyota CRDL
,
41
(
3
), pp. 15–21.
4.
Hunziker
,
R.
,
Dickmann
,
H.
, and
Emmrich
,
R.
,
2001
, “
Numerical and Experimental Investigation of a Centrifugal Compressor With an Inducer Casing Bleed System
,”
Proc. Inst. Mech. Eng., Part A
,
215
(
6
), pp.
783
791
.
5.
Qiu
,
X.
,
Krivitzky
,
E.
, and
Bollweg
,
P.
,
2012
, “
Meanline Modeling of Ported Shroud Centrifugal Compressors
,”
ASME
Paper No. GT2012-68915.
6.
Yamaguchi
,
S.
,
Yamaguchi
,
H.
,
Goto
,
S.
,
Nakao
,
H.
, and
Nakamura
,
F.
,
2002
, “
The Development of Effective Casing Treatment of Turbocharger Compressors
,”
Seventh International Conference on Turbochargers and Turbocharging
, London, IMechE Paper No. C602/008/2002.
7.
Tamaki
,
H.
,
2012
, “
Effect of Recirculation Device With Counter Swirl Vane of Performance of High Pressure Ratio Centrifugal Compressor
,”
ASME J. Turbomach.
,
134
(
5
), p. 051036.
8.
Tamaki
,
H.
,
Unno
,
M.
, and
Kawakubo
,
T.
,
2009
, “
Aerodynamic Design to Increase Pressure Ratio of Centrifugal Compressors for Turbochargers
,”
ASME
Paper No. GT2009-59160.
9.
Sivagnanasundaram
,
S.
,
Spence
,
S.
,
Early
,
J.
, and
Nikpour
,
B.
,
2013
, “
An Impact of Various Shroud Bleed Slot Configurations and Cavity Vanes on Compressor Map Width and the Inducer Flow Field
,”
ASME J. Turbomach.
,
135
(
4
), p. 041003.
10.
Yang
,
M.
,
Martinez-Botas
,
R.
,
Bamba
,
T.
,
Tamaki
,
H.
,
Zhang
,
Y.
,
Zheng
,
X.
, and
Li
,
Z.
,
2011
, “
Investigation of Self-Recycling-Casing-Treatment (SRCT) Influence on Stability of High Pressure Ratio Centrifugal Compressor With a Volute
,”
ASME
Paper No. GT2011-45065.
11.
Zheng
,
X.
,
Zhang
,
Y.
,
Yang
,
M.
,
Bamba
,
T.
, and
Tamaki
,
H.
,
2013
, “
Stability Improvement of High Pressure Ratio Turbocharger Centrifugal Compressor by Asymmetric Flow Control—Part II: Non-Axisymmetric Self Recirculation Casing Treatment
,”
ASME J. Turbomach.
,
135
(
2
), p.
021007
.
12.
Guillou
,
E.
,
Gancedo
,
M.
,
DiMicco
,
R. G.
,
Gutmark
,
E.
, and
Mohamed
,
A.
,
2011
, “
Surge Investigation in a Centrifugal Compressor by Stereoscopic PIV
,”
AIAA
Paper No. 2011-742.
13.
ANSYS Inc.
,
2013
, “
ANSYS CFX-Solver Theory Guide
,” Canonsburg, PA.
14.
Guillou
,
E.
,
2013
, “
Uncertainty and Measurement Sensitivity of Turbocharger Compressor Gas Stands
,”
SAE
Technical Paper No. 2013-01-0925.
15.
Khalid
,
S. A.
,
Khalsa
,
A. S.
,
Waitz
,
I. A.
,
Tan
,
C. S.
,
Greitzer
,
E. M.
,
Cumpsty
,
N. A.
,
Adamczyk
,
J. J.
, and
Marble
,
F. E.
,
1999
, “
Endwall Blockage in Axial Compressors
,”
ASME J. Turbomach.
,
121
(
3
), pp.
499
509
.
16.
Christou
,
G. A.
,
2015
, “
Fluid Mechanics of Ported Shroud Centrifugal Compressor for Vehicular Turbocharger Applications
,”
Ph.D. thesis
, Massachusetts Institute of Technology, Cambridge, MA.
17.
Hunziker
,
R.
, and
Gyarmathy
,
G.
,
1992
, “
The Operational Stability of a Centrifugal Compressor and Its Dependence on the Characteristics of the Subcomponents
,”
ASME
Paper No. 92-GT-284.
18.
Cumpsty
,
N. A.
,
2004
,
Compressor Aerodynamics
,
Krieger Publishing
,
Malabar, FL
.
19.
Greitzer
,
E. M.
,
Tan
,
C. S.
, and
Graf
,
M. B.
,
2004
,
Internal Flow Concepts and Applications
,
Cambridge University Press
, New York.
20.
Denton
,
J. D.
,
1993
, “
Loss Mechanisms in Turbomachines
,”
ASME J. Turbomach.
,
115
(
4
), pp.
621
656
.
You do not currently have access to this content.