Measurements are processed on a centrifugal pump model, which works with air and performs with the vane-island type diffuser of a real hydraulic pump, under five flow rates to investigate the internal flow characteristics and their influence on overall pump performance. The mean flow characteristics inside the diffuser are determined by using a miniature three-hole probe connected to an online data acquisition system. The flow structure at the inlet section of the diffuser is analyzed in detail, with a focus on the local pressure loss inside the vaneless gap and incidence angle distributions along the hub-to-shroud direction of the diffuser. Some existing calculations, including leakage effects, are used to evaluate the pressure recovery downstream of the impeller. Furthermore, particle image velocimetry (PIV) measurement results are obtained to help analyze the flow characteristics inside the vane-island diffuser. Each PIV measuring plane is related to one particular diffuser blade-to-blade channel and is analyzed by using the time-averaged method according to seven different relative positions of the impeller. Measurement results show that main loss is produced inside the vaneless part of the diffuser at low flow rates, which might have been caused by the strong rotor–stator interaction. When the impeller flow rate is greater than the diffuser design flow rate, a large fluctuating separated region occurs after the throat of the diffuser on the pressure side. Mean loss originates from the unsteady pressure downstream of the diffuser throat. For better characterization of the separations observed in previous experimental studies, complementary unsteady static pressure measurement campaigns have been conducted on the diffuser blade wall. The unsteadiness revealed by these measurements, as well as theirs effects on the diffuser performance, was then studied.

References

References
1.
Sinha
,
M.
, and
Katz
,
J.
,
1999
, “
Quantitative Visualization of the Flow in a Centrifugal Pump With Diffuser Vanes—Part I: On Flow Structures and Turbulence
,”
ASME J. Fluids Eng.
,
122
(
1
), pp.
97
107
.10.1115/1.483231
2.
Sinha
,
M.
,
Katz
,
J.
, and
Meneveau
,
C.
,
1999
, “
Quantitative Visualization of the Flow in a Centrifugal Pump With Diffuser Vanes—Part II: Addressing Passage-Averaged and Large-Eddy Simulation Modeling Issues in Turbomachinery Flows
,”
ASME J. Fluids Eng.
,
122
(
1
), pp.
108
116
.10.1115/1.483232
3.
Majidi
,
K.
,
2005
, “
Numerical Study of Unsteady Flow in a Centrifugal Pump
,”
ASME J. Turbomach.
,
127
(
2
), pp.
363
371
.10.1115/1.1776587
4.
Feng
,
J.
,
Benra
,
F. K.
, and
Dohmen
,
H. J.
,
2010
, “
Unsteady Flow Investigation in Rotor–Stator Interface of a Radial Diffuser Pump
,”
Forsch. Ingenieurwes.
,
74
(
4
), pp.
233
242
.10.1007/s10010-010-0128-x
5.
Akin
,
O.
, and
Rockwell
,
D.
,
1994
, “
Actively Controlled Radial Flow Pumping System: Manipulation of Spectral Content of Wakes and Wake–Blade Interactions
,”
ASME J. Fluids Eng.
,
116
(
3
), pp.
528
536
.10.1115/1.2910309
6.
Guleren
,
K. M.
, and
Pinarbasi
,
A.
,
2004
, “
Numerical Simulation of the Stalled Flow Within a Vaned Centrifugal Pump
,”
Proc. Inst. Mech. Eng., Part C
,
218
(
4
), pp.
425
435
.10.1177/095440620421800407
7.
Guo
,
S.
, and
Maruta
,
Y.
,
2005
, “
Experimental Investigations on Pressure Fluctuations and Vibration of the Impeller in a Centrifugal Pump With Vaned Diffusers
,”
JSME Int. J., Ser. B
,
48
(
1
), pp.
136
143
.10.1299/jsmeb.48.136
8.
Pavesi
,
G.
,
Cavazzini
,
G.
, and
Ardizzon
,
G.
,
2008
, “
Time–Frequency Characterization of the Unsteady Phenomena in a Centrifugal Pump
,”
Int. J. Heat Fluid Flow
,
29
(
5
), pp.
1527
1540
.10.1016/j.ijheatfluidflow.2008.06.008
9.
Furukawa
,
A.
,
Takahara
,
H.
,
Nakagawa
,
T.
, and
Ono
,
Y.
,
2003
, “
Pressure Fluctuation in a Vaned Diffuser Downstream From a Centrifugal Pump Impeller
,”
Int. J. Rotating Mach.
,
9
(
4
), pp.
285
292
.10.1155/S1023621X03000265
10.
Arndt
,
N.
,
Acosta
,
A. J.
,
Brennen
,
C. E.
, and
Caughey
,
T. K.
,
1990
, “
Experimental Investigation of Rotor/Stator Interaction in a Centrifugal Pump With Several Vaned Diffusers
,”
ASME J. Turbomach.
,
111
(
3
), pp.
213
221
.10.1115/1.2927428
11.
Eui
,
Y. K.
, and
Nam
,
H. C.
,
2001
, “
Experimental Study on the Mean Flow Characteristics of Forward—Curved Centrifugal Fans
,”
KSME Int. J.
,
15
(
12
), pp.
1728
1738
.10.1007/BF03185127
12.
Nakagawa
,
T.
,
Furukawa
,
A.
, and
Takahara
,
H.
,
2001
, “
Flow Behavior Downstream of Diffuser Pump Impeller
,”
ASME J. Turbomach.
,
29
(
2
), pp.
110
118
.
13.
Hong
,
S. S.
, and
Kang
,
S. H.
,
2004
, “
Flow at the Centrifugal Pump Impeller Exit With the Circumferential Distortion of the Outlet Static Pressure
,”
ASME J. Fluids Eng.
,
126
(
1
), pp.
81
86
.10.1115/1.1637630
14.
Petit
,
O.
, and
Nilsson
,
H.
,
2013
, “
Numerical Investigations of Unsteady Flow in a Centrifugal Pump With a Vaned Diffuser
,”
Int. J. Rotating Mach.
,
2013
, p.
961580
.10.1155/2013/961580
15.
Wuibaut
,
G.
,
Bois
,
G.
,
Dupont
,
P.
,
Caignaert
,
G.
, and
Stanislas
,
M.
,
2002
, “
PIV Measurements in the Impeller and the Vaneless Diffuser of a Radial Flow Pump in Design and Off-Design Operating Conditions
,”
ASME J. Fluids Eng.
,
124
(
3
), pp.
791
797
.10.1115/1.1486473
16.
Dupont
,
P.
,
Caignaert
,
G.
,
Bois
,
G.
, and
Schneider
,
T.
,
2005
, “
Rotor Stator Interactions in a Vaned Diffuser Radial Flow Pump
,”
ASME 2005 Fluids Engineering Division Summer Meeting
, Houston, Texas, June 19–23, pp.
1087
1094
.
17.
Atif
,
A.
,
Benmandsour
,
S.
,
Bois
,
G.
, and
Dupont
,
P.
,
2011
, “
Numerical and Experimental Comparison of the Vaned Diffuser Interaction Inside the Impeller Velocity Field of a Centrifugal Impeller
,”
Sci. China
,
54
(
2
), pp.
286
294
.10.1007/s11431-010-4260-5
18.
Cavazzini
,
G.
,
Pavesi
,
G.
,
Ardizzon
,
G.
,
Dupont
,
P.
,
Coudert
,
S.
,
Caignaert
,
G.
, and
Bois
,
G.
,
2009
, “
Analysis of the Rotor–Stator Interaction in a Radial Flow Pump
,”
La Houille Blanche
,
5
, pp.
141
151
.10.1051/lhb/2009067
19.
Cavazzini
,
G.
,
Dupont
,
P.
,
Dazin
,
A.
,
Pavesi
,
G.
,
Bayeul
,
A. C.
, and
Bois
,
G.
,
2013
, “
Unsteady Velocity PIV Measurements and 3D Numerical Calculation Comparisons Inside the Impeller of a Radial Pump Model
,”
10th European Conference on Turbomachinery-Fluid Dynamics and Thermodynamics
, Lappeenranta, Finland, Apr. 15–19, pp.
1
9
.
20.
Argüelles
,
D. K. M.
,
Fernández Oro
,
J. M.
, and
Marigorta Blanco
,
E.
,
2009
, “
Cylindrical Three-Hole Pressure Probe Calibration for Large Angular Range
,”
Flow Meas. Instrum.
,
20
(
2
), pp.
57
68
.10.1016/j.flowmeasinst.2008.12.001
21.
Barrand
,
J. P.
,
Caignaert
,
G.
,
Graesser
,
J. E.
, and
Rieutord
,
E.
,
1985
, “
Synthesis of the Results of Tests Air and Water Aimed at Critical Re-Circulating Flow Rates Detections on the Inlet and Outlet of a Centrifugal Impeller
,”
La Houille Blanche
,
5
.
22.
Cavazzini
,
G.
,
2006
, “
Experimental and Numerical Investigation of the Rotor–Stator Interaction in Radial Turbomachines
,” Ph.D. thesis, University of Padova, Padova, Italy.
23.
Idelchik
,
I. E.
,
2007
,
Handbook of Hydraulic Resistance
, 4th ed.,
Begell House, New York
.
24.
Bayeul
,
L. A. C.
,
Dupont
,
P.
,
Miccoli
,
L.
,
Cavazzini
,
G.
,
Dazin
,
A.
,
Pavesi
,
G.
, and
Bois
,
G.
,
2014
, “
Fluid Leakage Effect on Analysis of a Vaned Diffuser of SHF
,”
15th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery
, Honolulu, HI, Feb. 24–28, pp.
405
420
.
You do not currently have access to this content.