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Critical pressure condition at a nozzle throat Choose the correct statement about the steam velocity at the throat when the flow is critical (choked).

Q: Critical pressure condition at a nozzle throat Choose the correct statement about the steam velocity at the throat when the flow is critical (choked).

Concept/Approach At the critical pressure ratio, the mass flow is maximum and the Mach number at the throat is 1 (sonic), so velocity equals local speed of sound. Final Answer Equal to the velocity of sound

Difficulty: Easy

Equal to the velocity of sound
Less than the velocity of sound
More than the velocity of sound
None of these

Correct Answer: Equal to the velocity of sound

Explanation:

Concept/Approach

At the critical pressure ratio, the mass flow is maximum and the Mach number at the throat is 1 (sonic), so velocity equals local speed of sound.

Final Answer
Equal to the velocity of sound

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