This document compares reaction and impulse turbines. It states that impulse turbines use nozzles to direct steam onto curved buckets, extracting kinetic energy from the steam. Reaction turbines have fixed and moving blades with the steam gliding over both and losing pressure. The key differences are that impulse turbines use steam kinetic energy from nozzles while reaction turbines use both pressure and kinetic energy, and that impulse turbine blades are symmetrical while reaction turbine blades are asymmetrical. Most efficient steam turbines use a combination of impulse and reaction stages.
2. COMPARISON BETWEEN REACTION
AND IMPULSE TURBINE
Subject : Fluid Power Engineering
DE Group : 4
5th
Mechanical
Nisarg Amin (141080119002)
Akshay Patel(141080119031)
Abhimanyu Rathod (141080119041)
Aman Singh(141080119053)
3. What is a Turbine…??
• A machine for producing continuous power in
which a wheel or rotor, typically fitted with
vanes, is made to revolve by a fast-moving
flow of water, steam, gas, air, or other fluid.
• This mechanical energy is used in running an
electric generator which is directly coupled
the shaft of the turbine.
• Thus mechanical energy is converted to
electrical energy.
4. CLASSIFICATION OF TURBINE
1. According to type of energy at inlet.
2. According to direction of flow
through runner.
3. According to head at the inlet of
turbine.
4. According to specific speed of
turbine.
5. ACCORDING TO TYPE OF ENERGY AT
INLET
• On basis of the type of energy at inlet turbine
can be classified in two types.
1.Impulse turbine
2.Reaction turbine
6. IMPULSE TURBINE
• It runs by impulse of steam.
• Nozzle directs the steam on the curved blades,
which causes them to rotate. The blades are in
the shape of buckets.
• The energy to rotate an impulse turbine is
derived from the kinetic energy of the steam
flowing through the nozzle. The potential energy
is converted into kinetic energy when it passes
through the nozzle. The velocity of steam is
reduced when it passes over the blades.
7. REACTION TURBINE
• It has no nozzle.
• Two rows of moveable blades are separated
by one row of fixed blades.
• Fixed blades are attached to the casing & act
as nozzles. Blades are like the wings of a
plane.
8. COMPARISON BETWEEN REACTION
AND IMPULSE TURBINE
IMPULSE TURBINE
1. The steam flows through
the nozzle and impinges on
the moving blades.
2. The steam impinges on the
buckets with kinetic
energy.
3. The steam may or may not
be admitted over the
whole circumference.
4. Blades are symmetrical.
REACTION TURBINE
1. The steam flows through
guide mechanism and then
through moving blades.
2. The steam glides over
vanes with pressure and
kinetic energy.
3. The steam pressure is
reduced during the flow
through blades.
4. Blades are
unsymmetrical.
9. EFFICIENCY
• To maximize the efficiency of steam turbine
the steam is expanded, generating work in a
number of stages.
• Multiple stages turbines are highly efficient.
Most steam turbines use a mixture of both
impulse and reaction design.
• Higher pressure sections are impulse type
and lower pressure sections are reaction type.