MICHELL-BANKI
TURBINE
1. General Characteristics
The crossflow turbine or Michell-Banki turbine is primarily used for small hydroelectric utilities.
Its principle advantages are its simple design and ease of construction and its main attraction lies
in its low cost and potential to be used in small-scale operations.
However, this does not prevent the use of this type of turbine in large-scale installations. Although
the turbine is best known in small-scale applications, this kind of machine also exists in schemes
up to 6 MW.
The principle characteristics of this machine are:
It is adaptable to a wide range of spin speeds
The diameter of the turbine does not necessarily depend on the volume of the flow
One can reach an acceptable level of productivity with small turbines
It is possible to regulate the volume and power of the flow by way of an adjustable flier
2. Working Principles
The turbine consists of two principle elements: an injector and a rotor. The water is returned
through a flushing mechanism at atmospheric pressure. The rotor is composed of two parallel
discs, joined together by blades curved in circular sections.
Discharge
1st stage
2nd stage
Injector
Rotor
Figure 1: cross section of a Michell-Banki turbine
The nozzle has a cross-flow, rectangular section that is joined to the pipeline by a rectangular-
circular transition. This nozzle directs water towards the rotor through a section which accesses a
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