2. Definition
Hydraulic Turbine is a prime mover that
uses the energy of flowing water and
converts it into the mechanical energy in
the form of rotation of runner wheel.
Also termed as ‘water turbines’.
4. Classification
Based on hydraulic action of water
Based on direction of flow
Based on head of water and quantity of flow
Based on specific speed
Based on disposition of turbine shaft
Based on name of originator (commonly used
turbines)
5. Based on hydraulic action of water
Impulse turbine : One in which all the energy
of water is converted to kinetic energy before
the water strikes the vanes of the runner wheel.
This is done by passing the flow through nozzle
or some guidelines. The runner is rotated by the
force of water and water passes over the wheel
at atmospheric pressure.
Ex- Pelton Wheel
7. Reaction Turbine : Here, water entering the runner
wheel of the turbine has both kinetic energy and
pressure energy that is total head of water striking
the runner wheel ,consist partly of pressure head.
E.g- Francis turbine, Propeller turbine, Kaplan
turbine
9. Based on direction of flow
Radial flow turbine : A radial flow turbine is a turbine in
which the water as it move along the vane flow towards
the axis of rotation or away from it.
Radial flow turbine is of two types:
I. Inward flow turbine : If the flow of water is towards the
axis of rotation, its called inward flow turbine.
II. Outward flow turbine : If the flow of water is away from
the axis of rotation , its called outward flow turbine.
11. Axial flow turbine : Its the turbine in which water
enters the runner wheel parallel to the direction of
axis of rotation of runner.
Ex- Kaplan turbine, Propeller turbine
Tangential flow turbine : Its the turbine in which
water strikes the runner wheel tangentially to the
path of rotation.
Ex- Pelton turbine
13. Mixed flow turbine : It’s the turbine in which
the direction of flow is partly radial and partly
axial. Water enters the blade radially and
comes out axially parallel to the turbine shaft.
14. Based on head of water and
quantity of flow
High head turbine : when head is above 250 m
Ex- Pelton wheel
Medium head turbine : when head is between 60m – 250m
Ex- Francis turbine
Low head turbine : When head is between 15-60 m
Ex- kaplan turbine
Very low head turbine: When is head is less than 15m
Ex- Propeller turbine
15. Based on specific speed
Specific speed
10-35
35-60
60-300
300-1000
Types of turbine
Pelton wheel with one nozzle
Pelton wheel with two or more
nozzle, Multi jet pelton wheel
Francis turbine
Kaplan turbine
16. Based on disposition of turbine
shaft
Turbine shaft may be either vertical or
horizontal. Pelton turbine usually have
horizontal shafts whereas the rest have
vertical shafts.
17. Based on name of originator
Pelton wheel : Tangential flow impulse turbine used
for high head of water.
Francis turbine : Inward flow reaction turbine used
for medium head of water.
Kaplan turbine : Axial flow adjustable blades
reaction turbine used for low head of water.
Propeller turbine : Fixed blades axial flow reaction
turbine used for very low head of water.