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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:

Concept
In 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 Answer
Fixed and moving blades are identical (conjugate shapes)

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