Hydraulic turbines require a minimum head of water to operate and have several advantages including simple construction, easy controllability, and efficiency. They are classified based on the action of water on moving blades, direction of water flow, position of the shaft, head of water, speed, and specific speed. Impulse turbines have wheel passages not completely filled with water and water acts on buckets at atmospheric pressure, while reaction turbines have fully filled water passages and water acts under greater than atmospheric pressure all around the wheel periphery.

1. 09ME93 Yasir Hashmi
QUEST Nawabshah

2. HYDRAULIC TURBINES :
• Designed to work under a condition that head of
water should be above a certain minimum level.
• Without a certain minimum level of water in the
dam a turbine cannot be run.

3. ADVANTAGES :
• Simple construction
• Easily controllable
• Efficient
• Ability to work at peak load or stand by plant

4. CLASSIFICATION :
a. Based on action of water on moving
blades:
1. Impulse turbines
2. Reaction turbines
b. Direction of flow of water:
1. Tangential flow turbine
2. Radial flow turbine
3. Axial flow turbine
4. Mixed flow turbine

5. c. Position of shaft:
1. Vertical shaft turbines
2. Horizontal shaft turbines
d. Head of water:
1. High head turbines
2. Medium head turbines
3. Low head turbines
e. Based on speed:
f. Based on specific speed:

6. IMPULSE TURBINES:
• Wheel passages are not completely filled with water.
• Water acts on buckets at atmospheric pressure.
• Water is supplied on few points at the periphery of
wheel.
• How does it works?

7. REACTION TURBINES:
• Water passages are completely filled with water.
• Water acting on vanes is under pressure greater
than atmospheric.
• Water enters all round the periphery of wheel.
• How does it works?

8. THANKS