Question

Identify the correct combination of turbines classification based on the head of the water.

• A. A-P, B-R, C-Q
• B. A-R, B-P, C-Q
• C. A-P, B-Q, C-R
• D. A-Q, B-R, C-P

Hint:

Remember the general order of head suitability: Pelton (High Head)>Francis (Medium Head)>Kaplan (Low Head). Also, recall that Pelton is an impulse turbine, while Francis and Kaplan are reaction turbines.

Answer 1

The Correct Option is A

Step 1: Understand the classification of hydraulic turbines based on the head of water.
Hydraulic turbines are broadly classified based on the head of water under which they operate. The head refers to the difference in water level between the reservoir and the tailrace. Different types of turbines are suitable for different head ranges to achieve optimal efficiency. Step 2: Recall the typical head ranges for different types of turbines.
Pelton Wheel: This is an impulse turbine that is best suited for high heads (typically above 300 meters). It utilizes the kinetic energy of a high-velocity jet of water striking the buckets of the runner.
Francis Turbine: This is a reaction turbine suitable for medium heads (typically ranging from 30 to 300 meters). It operates with water flowing through the runner under pressure, with a change in both pressure and velocity.
Kaplan Turbine: This is also a reaction turbine, specifically designed for low heads (typically below 50 meters) with large volumes of water flow. It is a type of axial-flow turbine with adjustable runner blades. Step 3: Match the turbine types with their corresponding head ranges.
Based on the typical head ranges:
Pelton Wheel (A) is associated with High Head (P). So, A-P is a correct pairing.
Francis Turbine (B) is associated with Medium Head (R). So, B-R is a correct pairing.
Kaplan Turbine (C) is associated with Low Head (Q). So, C-Q is a correct pairing.
Step 4: Identify the option with the correct combination.
Looking at the given options:
Option (1) A-P, B-R, C-Q matches our findings.
Option (2) A-R, B-P, C-Q is incorrect because Pelton is for high head and Francis for medium head.
Option (3) A-P, B-Q, C-R is incorrect because Francis is for medium head and Kaplan for low head.
Option (4) A-Q, B-R, C-P is incorrect because Pelton is for high head and Kaplan for low head.
Therefore, the correct combination is A-P, B-R, C-Q.