Michell-Baniki turbine
Practical Action
VDI, 1981,
Ethiopia
Los Andes, 1973,
Colombia
ODTU, 1985,
Ankara, Turkey
0.67
0.62
0.83
3.26
1.87
1.44
36
27
30
66.00
60.60
55.50
In this table it can be seen that the optimum number of blades is between 24 and 30.
5. Calculation of the width of the rotor
An important factor to keep in mind is the calculation of the width of the rotor. This is calculated
with the selected diameter and the functioning parameters H and Q in mind.
As we know the area of admission is given by:
Aa = Q
Cml
Followed by
Aa = B.pz.Za
The step P, is given by:
(1)
(2)
If we define
Like the ratio between the number of blades for admission and the total number of blades, which
we will have after selecting the number of blades of the rotor, we could determine the number of
the admission blades, hence the value of xz
This number of blades already has a close link with the angle of admission of the machine.
The coefficient xz varies between 0.05 and 0.35. As a limit one adopts:
Equalizing (2) and (3) and resolving B we have:
In the end, what remains is the formula to calculate the width of the rotor:
4