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Head range suitability: Francis turbine selection Identify the usual range of available water head for which a Francis (mixed-flow reaction) turbine is preferred. Choose the correct range.

Q: Head range suitability: Francis turbine selection Identify the usual range of available water head for which a Francis (mixed-flow reaction) turbine is preferred. Choose the correct range.

Concept Francis turbines are medium-head mixed-flow reaction machines. Kaplan suits low head; Pelton suits high head. Typical ranges Francis: ≈ 25–250 m, depending on specific speed and site conditions. Final Answer 25 m to 250 m.

Difficulty: Easy

0 to 25 m
25 m to 250 m
Above 250 m
None of these

Correct Answer: 25 m to 250 m

Explanation:

Concept

Francis turbines are medium-head mixed-flow reaction machines.
Kaplan suits low head; Pelton suits high head.

Typical ranges
Francis: ≈ 25–250 m, depending on specific speed and site conditions.

Final Answer
25 m to 250 m.

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