Centrifugal Pump
Performance Experiment
Presented by: Steven King
ME 498 Senior lab
November 16, 2004
Overview of Presentation
 Objectives
 Methodology
and Background
 Experimental Setup
 Discussion of Results
 Conclusions and Recommendations
Objectives
 Become
familiar with centrifugal pump
operation
 Analyze the principles of fluid flow at
5 different shaft speeds
 Evaluate pump performance
Methodology and Background

Key Equations
B
(1) Cd  0.907  6.53
ReD
(2)
RED
Vt  2 D1


(3)
(4)
Vt  C d

Q  Cd AtVt
Assumptions: Β= .75, ρ=998, and μ=9.55x10-4
ΔP and was recorded during experiment.
0
(5)
2
 P2  P1   V2 2  V12 
 
Hp  
 Z 2  Z1 


2g
 g  

P
1   
4
Methodology and Background
Cont.
 Key Equations Continued
(6)

W pump  QP2  P1 
(7)
 pump
QP2  P1 

T
Affinity Laws
Q2  Q1
N2
N1
 N2 

Hp 2  Hp1 
 N1 
2
 N2 

P2  P1 
 N1 
3
Experimental Setup
Overall System Schematic
Experimental Setup Cont.
Experimental Setup Cont.
= 2 in
= 1.5 in
Venturi Flow Meter
Results

Uncertainty Values for Experiment


wQ = 38.0%
wη = 39.7%
Affinity Law Results
Value found
from
Experiment
Q (m3/s)
1165 RPM
%
Difference
5.61E-03
5.30E-03
5.55
P (W)
435.8
470.8
7.43
Hp (m)
7.92
9.06
12.58
7.49E-03
6.96E-03
7.12
P (W)
906.1
1066.4
15.03
Hp (m)
12.33
15.6
20.96
Q (m3/s)
1530 RPM
Calculated
Using Affinity
Laws
Results Cont.
Pump Head vs. Flow Rate
20
18
2
y = -130514x + 273.53x + 17.664
2
R = 0.999
16
Pump Head (m)
14
12
y = -109848x2 + 75.198x + 14.49
R2 = 0.9972
10
y = -123314x2 + 197.32x + 10.708
R2 = 0.9945
8
2
y = -37652x - 285.26x + 8.3396
2
R = 0.9714
6
900.2 RPM
992.8 RPM
4
2
y = -54121x - 192.77x + 7.0513
2
R = 0.9559
2
1165 RPM
1352 RPM
1530 RPM
0
1.5E-03
2.5E-03
3.5E-03
4.5E-03
5.5E-03
Flow Rate (m^3/s)
6.5E-03
7.5E-03
8.5E-03
Results Cont.
Pump Efficiency vs. Flow Rate
0.8
y = -9353.1x2 + 165.91x - 0.0087
R2 = 0.9985
0.7
0.6
Pump Efficiency
2
y = -19075x + 183.32x + 0.0023
2
R = 0.9955
0.5
y = -9886.8x2 + 151.87x - 0.0003
R2 = 0.9989
0.4
y = -15468x2 + 165.33x + 0.0014
R2 = 0.9976
0.3
y = -15032x2 + 166.37x - 0.0027
R2 = 0.9987
900.2 RPM
992.8 RPM
0.2
1165 RPM
1352 RPM
1530 RPM
0.1
0.0
0.0E+00
1.0E-03
2.0E-03
3.0E-03
4.0E-03
5.0E-03
Flow Rate (m^3/s)
6.0E-03
7.0E-03
8.0E-03
Results Cont.
Pump Efficiency vs. Pump Power to Fluid
0.8
0.7
2
y = -2E-06x2 + 0.0021x - 0.0003
R2 = 0.9996
y = -2E-07x + 0.001x + 0.0032
2
R = 0.9992
0.6
Pump Efficiency
2
y = -3E-06x + 0.0027x + 0.0008
2
R = 0.9985
2
y = -1E-06x + 0.0015x - 0.0017
2
R = 0.9988
2
y = -4E-08x + 0.0008x + 0.0009
2
R = 0.9999
0.5
0.4
0.3
0.2
900.2 RPM
992.8 RPM
1165 RPM
0.1
1352 RPM
1530 RPM
0.0
0
100
200
300
400
500
600
Pump Power (Watts)
700
800
900
1000
Results Cont.
Pump Power to Fluid vs. Flow Rate
1000
y = -1E+07x2 + 214130x - 15.3
R2 = 0.9978
900
Pump Power (Watts)
800
y = -1E+07x2 + 168878x - 8.0432
R2 = 0.9984
700
600
y = -8E+06x2 + 126678x - 4.5836
R2 = 0.9983
500
400
y = -5E+06x2 + 85850x - 0.3415
R2 = 0.999
300
900.2 RPM
200
y = -5E+06x2 + 73781x - 0.2309
R2 = 0.999
100
992.8 RPM
1165 RPM
1352 RPM
1530 RPM
0
0.0E+00
1.0E-03
2.0E-03
3.0E-03
4.0E-03
5.0E-03
Flow Rate (m^3/s)
6.0E-03
7.0E-03
8.0E-03
Conclusions and Recommendations




All R2 were above .95 with most being above .99
The best overall efficiency was approximately
70% for an RPM of 1530
The use of pressure gauges and dynamometer
that are less affected by vibration would improve
results
A more accurate method of recording voltage
and current would also improve the results