Manual for the Design of Pipe Systems and Pumps - GEA ...

6.4.2 Calculation of
correction
factors
Pumping medium: Oil
Flow rate: Q = 24 m 3/h
Flow head: H = 33 m
Viscosity: ν = 228 mm 2/s
Density: ρ = 0.9 t/m 3
Efficiency: η = 0.55 %
A vertical is set up cutting K H, K Q and K η at the intersection of the horizontal viscosity line
coming from the left side with the diagonal Q x √H line.
From each of the newly created intersections, a horizontal leads to the right hand side,
on to the correction factors. The reading is: K Q = 0.83, K H = 0.84, K η = 0.47
u
[mm2/s] 1000
8
6
4
3
2
100
8
6
4
3
2
10
8
6
4
3
2
100.000
1
Fig. 29 - Digram correction factors
Fill into the formula for the power consumption (Pz), the efficiency (η) from the „water flow
head diagram“.
Qz x Hz x ρ
power consumpt. Pz =
367 x Kη x η
Higher accuracy is achieved by repeating the procedure with the data obtained.
Result: After correction using the factors K Q, K H and K η, a pump must be selected for
pumping oil and a flow head of 24 m 3/h that is capapable of achieving 29 m 3/h and
39 m flow head. The required motor power is at least 7.5 kW.
31
GEA Tuchenhagen
10.000
Q x ÷H [m
0 8 6 4 3 2 0 8 6 4 3 2 0 8 6 4 3 2 0 8 6 4 3 2
3/h ÷m]
The pump should be designed for the following pump data based on water:
Q =
Qz KQ 24
0.83
Hz KH =
33
= 39.29 m
0.84 = = 28.9 m3/h; H =
=
24 x 33 x 0,9
367 x 0.47 x 0.55
1.000
100
= 7.52 kW
10
K h
K Q
K H
1
0
6
4
Korrekturfaktor
2
1,0
0,9
0,8
0,7
0,6
0,5
0,4
0,3
0,2
0,1
0