THEORY

One of the most common radial-flow turbo machines in the centrifugal pump. This type of pump has two main components: an impeller attached to a rotating shaft, and a stationary casting (or housing) enclosing the impeller. Schematic diagram of basic elements of centrifugal pump is as shown below.

 

Consider the experimental arrangement for determining the head rise (or pressure rise) gained by fluid flowing through a pump, as shown in figure below.

 

			Impeller

 

 

 

Eye

Inflow

Blade

Hub plate

	Casing, housing or volute

 

 

 

Figure 1: Basic Elements of Centrifugal Pump

 

 

Figure 1.1 Experimental Arrangements for Pump Performance Characteristic.

 

 

 

The pump head rise can be expressed using the energy equation as,

           

Typically the differences in elevations and velocities (between inlet and outlet) are so small that,

           

The power,

The pump overall efficiency, is the ratio of power actually gained by the fluid to the shaft power supplied () as given by the equation,

 

 

Figure 1.2 The Motor of the Centrifugal Pump