DIFFUSER OR TURBINE PUMP D014
In recent years these pumps have been called deep well turbine pumps because of their application.
A series of vanes around the volute reduce radial deflection of the shaft any time the pump operates off of its best efficiency point (BEP).
The designer tries to select one more diffuser vane than the number of vanes on the impeller. This will reduce circulation around the diffuser vanes resulting from uneven impeller discharge.
The diffuser is seldom applied to a single stage, radial flow pump.
The picture on the left shows the diffuser configuration.
With the exception of some multistage high-pressure pump designs, the application is limited to vertical turbine pumps and single stage low head propeller pumps.