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Blade geometry in a Parsons reaction turbine For a Parsons (≈50% reaction) turbine stage, determine the relation between fixed (stator) and moving (rotor) blade shapes. Choose the correct option.

Difficulty: Easy

Only moving blades are present
Only fixed blades are present
Fixed and moving blades are identical (conjugate shapes)
Fixed and moving blades have different shapes

Correct Answer: Fixed and moving blades are identical (conjugate shapes)

Explanation:

ConceptIn a Parsons reaction stage (degree of reaction ≈ 0.5), the fixed and moving blade passages are designed to be geometrically similar so that pressure drop and acceleration are shared equally.

Final AnswerFixed and moving blades are identical (conjugate shapes)

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