Sudden fluid expansion into a vacuum through a large orifice is termed___________________?
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Answer: A. free expansion
Explanation
Free expansion occurs when a fluid rushes into an evacuated chamber. No external mechanical work is performed because the boundary does not move. The process is highly irreversible due to unresisted fluid expansion. Joule performed famous free expansion experiments using connected gas vessels. Internal energy remains constant during free expansion of an ideal gas. The expanding fluid encounters zero opposing force during the motion.
Pipeline rupture scenarios often involve rapid free expansion of pressurized gases. Vacuum system design requires understanding sudden gas expansion dynamics. Safety relief valves sometimes experience free expansion characteristics during failure. Option B describes hyperbolic processes which relate to isothermal gas behavior. Option C is incorrect because free expansion is distinctly irreversible and unresisted. Option E throttling involves flowing through a restricted passage, unlike free expansion.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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