Difficulty: Easy
Correct Answer: Discharge pressure
Explanation:
Introduction / Context:Clear terminology is essential when reading compressor specifications and performance curves. The pressure measured at the outlet nozzle or delivery header of a compressor is a standard data point used to define pressure ratio and duty.
Given Data / Assumptions:
Concept / Approach:The absolute pressure at the compressor outlet is called the discharge pressure. It is paired with the inlet (suction) pressure to define the compression ratio: r = p_out / p_in. The term “back pressure” is used in different contexts (e.g., exhaust systems), and “critical pressure” relates to choked flow theory, not compressor outlet nomenclature.
Step-by-Step Solution:
Identify location: outlet side of compressor.Identify quantity: absolute pressure.Standard term: discharge pressure.Verification / Alternative check:Compressor datasheets list suction pressure, discharge pressure, and pressure ratio; these terms are universally used in industry standards.
Why Other Options Are Wrong:
Back pressure: generic term for resistance pressure downstream, not the designated outlet absolute pressure term.Critical pressure: relates to nozzle choking, not outlet measurement naming.Atmospheric or stagnation pressures are not the specific descriptor for outlet line pressure in this context.
Common Pitfalls:Confusing gauge and absolute units; always check whether the specification uses bar(a) or bar(g).
Final Answer:
Discharge pressure
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