Turbine and its Classification

Turbine

Turbine is a device that extracts energy from a fluid (converts the energy held by the fluid to mechanical energy)

• Pumps are devices that add energy to the fluid (e.g. pumps, fans, blowers, and compressors)  
• Hydroelectric power is the most remarkable development pertaining to the exploitation of water resources throughout the world.
• Hydroelectric power is developed by hydraulic turbines which are hydraulic machines.
• Turbines convert hydraulic energy or hydro-potential into mechanical energy.
• The mechanical energy developed by turbines is used to run electric generators coupled to the shaft of turbines.
• Hydroelectric power is the cheapest source of power generation.

  Classification of turbines

 1: On the basis of hydraulic action or type of energy at the inlet

•  Impulse Turbine (Pelton Wheel)
•  Reaction Turbine (Francis Turbine)

 2: On the basis of the direction of flow through the runner

• Tangential flow turbine (Pelton)
• Radial flow turbine (Francis )
• Axial Flow Turbine (Kaplan)
• Mixed flow turbine (Modern Francis)  

3: On the basis of the head of water

• High head turbine (Pelton, H>250m)
• Medium head turbine (modern Francis, 60-250m)
•  Low head turbine (Kaplan, <60m)

4: On the basis of specific speed Ns of the turbine

•  Low specific speed (Pelton, 10-35)
•  Medium (Francis, 60-400)
• High specific speed (Kaplan, 300-1000)