Today we will discuss about main difference
between impulse and reaction turbine. In my last post we have learnt about main
types of turbine. We know that turbines are widely used in power generation
industries. Selection of proper hydraulic turbine is among the most important factor
affecting the economic viability of hydraulic project.
The term impulse and reaction denote the
basic type of turbine. The basic and main difference between impulse and
reaction turbine is that there is pressure change in the fluid as it passes
through runner of reaction turbine while in impulse turbine there is no
pressure change in the runner. In the impulse turbine first all pressure energy
of water convert into the kinetic energy through a nozzle and generate a high
speed jet of water. This water jet
strikes the blade of turbine and rotates it. In the reaction turbine there is pressure
change of water when it passes through the rotor of turbine. So it uses kinetic
energy as well as pressure energy to rotate the turbine. Due to this it is known
as reaction turbine.
Difference between Impulse and Reaction Turbine:
Impulse
Turbine
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Reaction
Turbine
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1.
In impulse turbine only kinetic energy is used to rotate the turbine.
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1. In reaction turbine both kinetic and pressure
energy is used to rotate the turbine.
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2. In this turbine water flow through the
nozzle and strike the blades of turbine.
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2. In this turbine water is guided by the
guide blades to flow over the turbine.
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3. All pressure energy of water converted
into kinetic energy before striking the vanes.
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3. In reaction turbine, there is no change in
pressure energy of water before striking.
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4. The pressure of the water remains
unchanged and is equal to atmospheric pressure during process.
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4. The pressure of water is reducing
after passing through vanes.
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5. Water may admitted over a part of circumference
or over the whole circumference of the wheel of turbine.
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5. Water may admitted over a part of circumference
or over the whole circumference of the wheel of turbine.
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6. In impulse turbine casing has no hydraulic
function to perform because the jet is at atmospheric pressure. This casing
serves only to prevent splashing of water.
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6. Casing is absolutely necessary because
the pressure at inlet of the turbine is much higher than the pressure at outlet.
It is sealed from atmospheric pressure.
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7. This turbine is most suitable for
large head and lower flow rate. Pelton wheel is the example of this turbine.
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7. This turbine is best suited for higher
flow rate and lower head situation.
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Today we have discussed about Difference between impulse and reaction turbine. If you have any query kindly ask by commenting.