This paper reports an experimental investigation of the rotordynamic fluid force and moment on a centrifugal impeller with three types of wear-ring seals; i.e., a face seal and two types of toothed seals. The impeller is equipped with a vaneless diffuser. Rotordynamic fluid forces and moments on the impeller in whirling motion were measured directly by using four-axis force sensor. Unsteady pressures were measured at several locations in the diffuser. It was found that, (1) at low flow rate, the fluid force and fluid force moment become maximum at a certain whirling speed caused by a coupling between the whirl motion and vaneless diffuser rotating stall and (2) the seal geometry with axial seal affects the direction of the coupled fluid force relative to the direction of eccentricity through the change in the unsteady leakage flow due to the whirl.

1.
Jery, B., Acosta, A. J., Brennen, C. E., and Caughy, T. K., 1985, “Forces on Centrifugal Pump Impellers,” Proceedings of the 2nd International Pump Symposium, Houston, TX, pp. 21–32.
2.
Bolleter
,
U.
,
Wyss
,
A.
,
Whelte
,
I.
, and
Sturchler
,
R.
,
1987
, “
Measurement of Hydraulic Interaction Matrices of Boiler Feed Pump Impeller
,”
ASME J. Vib., Acoust., Stress, Reliab. Des.
,
109
, pp.
144
151
.
3.
Ohashi, H., Sakurai, A., and Nishihama, J., 1988, “Influence of Impeller and Diffuser Geometries on the Lateral Fluid Forces of Whirling Centrifugal Impeller,” NASA CP. 3026, pp. 285–306.
4.
Adkins
,
D. R.
, and
Brennen
,
C. E.
,
1988
, “
Analyses of Hydraulic Radial Forces on Centrifugal Pump Impeller
,”
ASME J. Fluids Eng.
,
110
, pp.
20
28
.
5.
Tsujimoto
,
Y.
,
Acosta
,
A. J.
, and
Brennen
,
C. E.
,
1988
, “
Theoretical Study of Fluid Forces on Centrifugal Pump Impeller Rotating and Whirling in a Volute
,”
ASME J. Vib., Acoust., Stress, Reliab. Des.
,
110
, pp.
263
269
.
6.
Tsujimoto, Y., Acosta, A. J., and Yoshida, Y., 1988B, “A Theoretical Study of Fluid Forces on Centrifugal Pump Impeller Rotating and Whirling in a Vaned Diffuser,” NASA CP. 3026, pp. 307–322.
7.
Childs
,
D. W.
,
1989
, “
Fluid Structure Interaction Forces at Pump-Impeller-Shroud Surfaces for Rotordynamic Calculation
,”
ASME J. Vib., Acoust., Stress, Reliab. Des.
,
109
, pp.
144
151
.
8.
Guinzburg
,
A.
,
Brennen
,
C. E.
,
Acosta
,
A. J.
, and
Caughy
,
T. K.
,
1994
, “
Experimental Results for the Rotordynamic Characteristics of Leakage Flow in Centrifugal Pump
,”
ASME J. Fluids Eng.
,
116
, pp.
110
115
.
9.
Uy
,
R. V.
, and
Brennen
,
C. E.
,
1999
, “
Experimental Measurements of Rotordynamic Forces Caused by Front Shroud Pump Leakage
,”
ASME J. Fluids Eng.
,
121
, pp.
633
637
.
10.
Ohashi, H., Imai, H., Sakurai, A., and Nishihama, J., 1990, “Lateral Fluid Forces of Whirling Centrifugal Impellers With Various Geometries,” The 3rd Japan-China Joint Conference of Fluid Machinery, 11, pp. 147–153.
11.
Bently, D. E., and Goldman, P., 1998, “Destabilizing Effect of Aerodynamic Forces in Centrifugal Compressors,” Proceedings of the 7th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Honolulu HI, A, pp. 306–315.
12.
Yoshida
,
Y.
,
Tsujimoto
,
Y.
,
Ishi
,
N.
,
Ohashi
,
H.
, and
Kano
,
F.
,
1999
, “
The Rotordynamic Forces on an Open-Type Centrifugal Compressor Impeller in Whirling Motion
,”
ASME J. Fluids Eng.
,
121
, pp.
259
265
.
13.
Bolleter, U., Leibundgut, E., Sturchler, R., and McCloskey, L., 1989, “Hydraulic Interaction and Excitation Forces of High Head Pump Impellers,” Proc. of the 3rd Joint ASCE/ASME Mechanical Conference, pp. 187–193.
14.
Shoji
,
H.
, and
Ohashi
,
H.
,
1987
, “
Lateral Fluid Forces on Whirling Centrifugal Impeller (1st Report: Theory)
,”
ASME J. Fluids Eng.
,
109
, pp.
94
99
.
15.
Shoji
,
H.
, and
Ohashi
,
H.
,
1987
, “
Lateral Fluid Forces on Whirling Centrifugal Impeller (2nd Report: Experiment in Vaneless Diffuser)
,”
ASME J. Fluids Eng.
,
109
, pp.
100
106
.
16.
Tsujimoto, Y., and Acosta, A. J., 1987, “Theoretical Study of Impeller and/or Vaneless Diffuser Attributed Rotating Stall and Their Effects on Whirling Instability of Centrifugal Impeller,” Work Group on the Behavior of Hydraulic Machinery under Steady Oscillatory Conditions, Lille, France.
17.
Tsujimoto
,
Y.
,
Yoshida
,
Y.
, and
Mori
,
Y.
,
1994
, “
Study of Vaneless Diffuser Rotating Stall Based on Two-Dimensional Inviscid Flow Analysis
,”
ASME J. Fluids Eng.
,
118
(
1
), pp.
123
127
.
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