Working principle of reaction turbines - Basic Mechanical Engineering

Q.  Which of the following statements are false for reaction turbines?

1. Flow of water can be regulated without any losses
2. It works on the principle of impulse and reaction
3. They are suitable for low heads
4. Water flows at constant atmospheric pressure over the runner

- Published on 01 Sep 15

a. 1, 2 and 3
b. 2 and 4
c. 1 and 4
d. 1, 2, 3 and 4

ANSWER: 1 and 4


  • Sravanthi    -Posted on 12 Nov 15
    - Reaction turbines:

    - In reaction turbines, water enters the runner under pressure which has some velocity head. Mechanical work is produced when runner rotates, this rotation occurs due to the pressure difference and the impulse action.

    - These turbines work on the principle of impulse and reaction. They work part on kinetic energy and partly on hydraulic pressure energy but maximum work is done due to change in pressure head and minimum work is done due to change in kinetic energy. Flow of water can be regulated without any loss in impulse turbines and not in reaction turbines.

    - Reaction turbines are suitable for low and medium heads. They require casing as water flows from inlet to outlet pressure. The pressure gradually decreases from inlet to outlet as water flows under pressure over the runner.

    - Reaction turbines use draft tubes to recover head loss due to installation above tail race.

Post your comment / Share knowledge

Enter the code shown above:
(Note: If you cannot read the numbers in the above image, reload the page to generate a new one.)