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Energy conversion in a reaction turbine runner Assess the statement: As water flows over the vanes of a reaction turbine, its pressure head decreases and is converted into kinetic head before leaving the wheel. Choose the correct judgment.

Difficulty: Easy

True
False
True only at part load
False unless a draft tube is used

Correct Answer: True

Explanation:

Concept

In a reaction turbine (e.g., Francis, Kaplan), pressure drop occurs across the runner itself.

Energy changes
As water passes through the moving passages, part of its pressure head converts to kinetic head and mechanical work on the runner.Residual velocity head at exit is then partially recovered by the draft tube.

Final Answer
True.

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