Difference Between Impulse and Reaction Turbine

In this article, we will discuss all the major difference between impulse and reaction turbine. Both types of turbine are used in power plants for the generation of electricity. Instead of their same work of producing electricity, they are differing from each other in much respect. Here we will discuss various differences among them in detail.

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Difference Between Impulse and Reaction Turbine

S.no	Impulse Turbine	Reaction Turbine
1.	In an impulse turbine, the steam flows through the nozzle and strike on the moving blades.	In the reaction turbine, first, the steam flows through the guide mechanism and then flows through the moving blades.
2.	Steam strikes on the buckets with kinetic energy.	The steam glides over the moving blades with both pressure and kinetic energy.
3.	During the flow of steam through moving blades, its pressure remains constant.	During the flow of steam through moving blades its pressure reduces.
4.	The steam may or may not be admitted to the whole circumference.	The steam must be admitted over the whole circumference.
5.	The blades of impulse turbine are symmetrical.	The blades of reaction turbine are not symmetrical.
6.	While gliding over the blades the relative velocity of steam remains constant.	In reaction turbine, while gliding over the blades the relative velocity of steam increases.
7.	For the same power developed, the number of stages required is less.	For the same power developed, the number of stages required is more.
8.	The direction of steam flow is radial to the direction of turbine wheel.	The direction of steam flow is radial and axial to the turbine wheel.
9.	It requires less maintenance work.	It requires more maintenance work.
10.	It is suitable for low discharge.	It is suitable for medium and high discharge.
11.	Pelton Wheel is the example of impulse turbine.	Francis turbine, Kaplan turbine etc. are the examples of reaction turbine.

Comparison Between Impulse and Reaction Turbine

In impulse turbine the steam flows through the nozzle and strikes on the moving blades. In reaction turbine steam first flows through the guide mechanism and then flows through the moving blades.

In impulses turbine, steam strikes on the moving blades with kinetic energy only. But in the reaction turbine, the steam which glides over the moving blades possesses both pressure and kinetic energy.
In impulse turbine the pressure of steam remains constant during its flow through the moving blades. But in reaction turbine, the pressure of steam reduces during its flow through the moving blades.

In impulse turbine the steam may or may not be admitted to the whole circumference. In reaction turbine the steam must be admitted to the whole circumference.
The blades of the impulse turbine are symmetrical where as in reaction turbine it is not symmetrical.
The relative velocity of steam in impulse turbine remains constant but in Reaction turbine it increases while gliding over the blades.

For the same power developed, the number of stages required in impulse turbine is less where as in reaction turbine the number of stages required is more.
The steam flow in impulse turbine is radial to the turbine wheel where as in reaction turbine steam flow is radial and axial to the turbine wheel.
If we talk about the maintenance work, then impulse turbine has less maintenance work as compared with the reaction turbine.

Impulse turbine is suitable where discharge is low and reaction turbine is suitable for medium and high discharge.
Pelton wheel is the example of impulse turbine whereas Francis turbine, Kaplan turbine etc. are the examples of reaction turbine

This is the difference between impulse turbine and reaction turbine. If you have any query related to this article than comment us. If you find this article useful than don’t forget to like us on Facebook and Google+.