In this paper the three-dimensional inverse design code TURBOdesign-1 is applied to the design of the blade geometry of a centrifugal compressor impeller with splitter blades. In the design of conventional impellers the splitter blades normally have the same geometry as the full blades and are placed at mid-pitch location between the two full blades, which can usually result in a mismatch between the flow angle and blade angles at the splitter leading edge. In the inverse design method the splitter and full blade geometry is computed independently for a specified distribution of blade loading on the splitter and full blades. In this paper the basic design methodology is outlined and then the flow in the conventional and inverse designed impeller is compared in detail by using computational fluid dynamics (CFD) code TASCflow. The CFD results confirm that the inverse design impeller has a more uniform exit flow, better control of tip leakage flow and higher efficiency than the conventional impeller. The results also show that the shape of the trailing edge geometry has a very appreciable effect on the impeller Euler head and this must be accurately modeled in all CFD computations to ensure closer match between CFD and experimental results. Detailed measurements are presented in part II of the paper.

1.
Drtina, P., Dalbert, P., Rutti, K., and Schachenmann, A., 1993, “Optimization of a Diffuser With Splitter by Numerical Simulation,” ASME Paper 93-GT-110.
2.
Zangeneh
,
M.
,
1991
, “
A Compressible Three Dimensional Blade Design Method for Radial and Mixed Flow Turbomachinery Blades
,”
Int. J. Numer. Methods Fluids
,
13
, pp.
599
624
.
3.
Zangeneh, M., 1998, “On 3D Inverse Design of Centrifugal Compressor Impellers With Splitter Blades,” ASME Paper 98-GT-507.
4.
Zangeneh
,
M.
,
Goto
,
A.
, and
Harada
,
H.
,
1998
, “
On the Design Criteria for Suppression of Secondary Flows in Centrifugal and Mixed Flow Impellers
,”
ASME J. Turbomach.
,
120
, pp.
723
735
.
5.
Zangeneh
,
M.
,
Goto
,
A.
, and
Harada
,
H.
,
1999
, “
On the Role of Three-Dimensional Inverse Design Methods in Turbomachinery Shape Optimization
,”
Proc. IMECHE Part C, J. Mech. Eng. Sci.
,
213
(
C1
), pp.
27
42
.
6.
Zangeneh, M., Vogt, D., and Roduner, C., 2002, “Improving a Vaned Diffuser for a Given Centrifugal Impeller by 3D Inverse Design,” ASME Paper GT-2002-30621.
7.
Schleer, M., Hong, S., Zangeneh, M., Roduner, C., Ribi, B, Ploger, F., and Abhari, R. S. 2004, “Investigation of an Inversely Designed Centrifugal Compressor Stage–Part II: Experimental Investigations,” ASME J. Turbomach., 126, pp. 82–90.
8.
Hunziker, R., and Gyarmathy, G., 1993, “The Operational Stability of a Centrifugal Compressor and Its Dependence on the Characteristics of the Sub-Components,” ASME Paper 93-GT-284.
9.
Dalbert, P., Gyarmathy, G., and Sebestyen, A., 1993, “Flow Phenomena in Vaned Diffuser of a Centrifugal Stage,” ASME Paper 93-GT-53.
10.
Roduner, C., Koppel, P., Kupferschmied, P., and Gyarmathy, G., 1998, “Comparison of Measurement Data at the Impeller Exit of Centrifugal Compressor Measured With Both Pneumatic and Fast Response Probes,” ASME Paper 98-GT-241.
11.
Dawes, W. N., 1988, “The Development of a 3D Navier-Stokes Solver for Application to all Types of Turbomachinery,” ASME Paper 88-GT-70.
12.
TASCflow, 1999, Version 2.10 documentation, AEA Technology Ltd., London.
13.
Goto
,
A.
, and
Zangeneh
,
M.
,
2002
, “
Hydrodynamic Design of Pump Diffuser Using Inverse Design Method and CFD
,”
ASME J. Fluids Eng.
,
124
, pp.
319
328
.
14.
Roduner, C., 2002, private communications.
15.
Ribi, B, 2002, private communications.
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