Brochure
Performance curvesImpeller shape
n
q
15
30
50
90
110
Outlet velocity
triangle
P
d
H
100
45
Q/Q
d
130100
0
P
d
H
100
60
Q/Q
d
1401000
P
d
H
Q/Q
d
1551000
H
110 P
100 P
d
Q/Q
d
1651000
%
%
%
P
d
P
d
P
H
H
130 P
100 P
d
100
100
80
70
100
55
H
d
Q/Q
d
1701000
%
H
H
d
%
H
H
d
d
2
/d
1
= 3.5 - 2.0
d
2
/d
1
= 2.0 - 1.5
d
2
/d
1
= 1.5 - 1.3
d
2
/d
1
= 1.2 - 1.1
d
1
= d
2
d
2
C
2
C
2U
C
2
C
2U
C
2
C
2U
C
2
C
2
C
2
C
2U
C
2U
C
2U
U
2
W
2
U
2
W
2
W
2
W
2
W
2
W
2
U
2
U
2
U
2
U
2
d
2
d
2
d
2
d
2
d
1
d
1
d
1
d
1
d
1
100 P
80 P
d
%
%
H
H
d
%
H
H
d
100 P
70 P
d
%
100 P
65 P
d
%
75
75
4.9 Summary
In this chapter we have described the basic physical conditions which are the
basis of any pump design. Euler’s pump equation has been desribed, and we
have shown examples of how the pump equation can be used to predict a
pump’s performance. Furthermore, we have derived the anity equations
and shown how the anity rules can be used for scaling pump performance.
Finally, we have introduced the concept of specific speed and shown how
dierent pumps can be dierentiated on the basis of this.
Figure 4.17: Impeller shape, outlet velocity
triangle and performance curve as function
of specific speed n
q
.