all about Francis turbine

2. *

3. *
• Steam turbine
Water turbine
Wind turbine

4. Impulse Turbine
Reaction Turbine
Only Kinetic Energy of water is used to drive turbine .
Eg. Pelton Turbine
Kinetic Energy as well as pressure energy of water is used to
drive turbine .
Eg. Francis Turbine

5. Impulse Turbine Reaction Turbine
Power is obtained only
due to the impulsive force
of the incoming steam
Power is obtained due to
impulsive force of
incoming steam as well as
reaction of exit steam
Suitable for small
capacity of power
generation & occupies
less space per unit power
Suitable for medium &
high capacity power
generation and occupies
more space per unit
power
Efficiency is lesser Efficiency is higher
Compounding is necessary
to reduce speed
Compounding is not
necessary

6. Depending upon the direction of flow through the runner, following types of
turbines are
a) Tangential flow turbines
b) Radial flow turbines
c) Axial flow turbines
d) Mixed flow turbines
Based on direction of flow of water in the runner

7. *
*After electric generators were developed in
the late 1800s turbines were a natural
source of generator power.
*In 1826 Benoit Fourneyron developed a high
efficiency (80%) outward-flow water
turbine, Named boydon turbine.

8. *but was not enough In 1848 James B. Francis,
while working as head engineer of the Locks and
Canals company, improved on these designs to
create more efficient turbines and named boydon
turbine as francis turbine…
*Nineteenth-century efficiency improvements of
water turbines allowed them to replace nearly all
water turbine applications.

9.  A turbine is a rotary mechanical device that extracts energy from fluid flow and convert it into useful work.
 Francis turbine was developed by James B. Francis.
 Francis turbines are the most common water turbine in use today .
 Water enters the turbine through the outer periphery of the runner in the radial direction and leaves the
runner in the axial direction.
Francis turbine is also called as mixed flow turbine ( radial flow + axial flow )

10. FANCIS TURBINES

11. Components of Francis Turbine
: It constitutes a closed passage whose cross-section area gradually decreases along the
flow direction, area is maximum at inlet and zero at exit.
Absorbs the energy from the water and converts it to rotational motion of the main shaft.
: provide drainage space.
: Prevent water leakage between main shaft and head cover.
: provides encased water path to contain the water pressure

12. Components and it’s functions
 Runner Blade :: Absorbs the energy from the water and
converts it to rotational motion of the main shaft.
Draft Tube :: It is a gradually expanding tube which
discharges water, passing through runner, to the tail race.

13. The water is entered by the guide blades into the
revolving turbine or wheel, the water while gliding
over the blades exerts some force on the revolving
wheel ,to which the vanes are fixed….this force
causes the revolving wheel to revolve.

14. 

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g
V
h
g
V
h
Losseshydraulic
g
V
h
g
V
h
hydraulic
22
22
2
3
3
2
1
1
2
3
3
2
1
1


15. Part-flow efficiency of small hydraulic turbines
Cross-
flow
Pelton
Kaplan
Francis Propeller
0.0 0.2 0.4 0.6 0.8 1.0
1.0
0.8
0.6
0.4
0.2
0.0
Flow rate as proportion of design flow rate
Maximum and minimum turbine flow rates to be decided based on turbine size
and efficiency curve.

16. *INSTALLATION OF FRANCIS TURBINE

19. *Francis Turbine Power Plant : A Continuous
Hydraulic System

20. Advantages of Francis
Turbine
 It is mostly used turbine all over the world as its efficiency is greater than all other
turbines.
 There is an effective use of water pressure and velocity.
 It is now an American Standard Turbine.
 Its efficiency is nearly 94% when used to the Everest.

21. Disadvantages of Francis Turbine
*Its cost is very high.
*Its operation is simple but the design is very complex.
*Large number of moving parts are present.
*Its maintenance and repair is difficult task and expensive too.
*It is applicable to medium head levels only.

22. *
*At first, F.turbine was used in industries to drive the
machines via belts.
*It is used in dams and water reservoirs to generate
hydroelectric power.
*Used to pump the water up when there is not much
electricity needed.

23. We use New types of designs to reduce the cost and complexity of mechanism.
 Modified turbine include lnline Link less Francis turbine, Cross flow turbine
 These new turbine require less space, simplified designed , less moving parts, etc.