Solve this multiple-choice question and choose the correct option.

Concept/Approach An ideal nozzle converts enthalpy drop into kinetic energy with no heat transfer or irreversibility; thus the expansion is modeled as isentropic. Pressure and density change; volume is not constant, and the process is not isothermal in general. Final AnswerIsentropic flow

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Nature of flow through a well-designed nozzle Assume steady, adiabatic expansion with negligible potential energy change and small friction. How is the flow commonly idealized?

Difficulty: Easy

Constant-volume flow
Constant-pressure flow
Isothermal flow
Isentropic flow

Correct Answer: Isentropic flow

Explanation:

Concept/Approach

An ideal nozzle converts enthalpy drop into kinetic energy with no heat transfer or irreversibility; thus the expansion is modeled as isentropic.
Pressure and density change; volume is not constant, and the process is not isothermal in general.

Final AnswerIsentropic flow

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