Impulse and reaction turbines types are used in electricity generation plants. They differ widely from each other rather than from their work in producing electricity.

Difference between impulse and reaction turbine

Impulse turbine: 

• Steam flows through the nozzle in the impulse turbine and falls on the rotating blades.
• In impulses turbine, steam reaches the rotating blades with kinetic energy only.
• The pressure of the steam in the impulse turbine remains constant during its passage through the rotating blades.
• Steam can be admitted to the entire circumference and not in the impulsive turbine.
• The blades of the impulse turbine are symmetrical.
• The relative steam velocity remains constant in the impulse turbine.
• Impulse turbine is suitable where discharge is low.
• Impulse turbine requires less maintenance than a reaction turbine.
• In an impulse turbine, steam flow is radial to the turbine wheel
• Pelton wheel is one the example of impulse turbine

Reaction turbine: 

• In the reaction turbine, the steam flows first through the guidance system and then through the rotating blades.
• The steam which floats over the moving blades has both pressure and kinetic energy in the reaction turbine.
• In a reaction turbine, the pressure of steam decreases during its flow through the moving blades.
• The steam must be applied to the entire circumstances of the reaction turbine.
• The reaction turbines are not symmetrical compared to the impulse turbine.
• The relative steam velocity in reaction turbine is increased while slithering over the blades.
• The steam flow in reaction turbine is radial and axial to the turbine wheel.
• In comparison to impulse turbine, more maintenance is required.
• Turbine reaction suits for medium and high discharge.
• Francis turbine and Kaplan turbine are some of the examples of the reaction turbine.