Difficulty: Easy
Correct Answer: False
Explanation:
Introduction / Context:
“Free air delivery” (FAD) is a standardized term essential for comparing compressors. It is often misstated as just the raw delivered volume, which causes confusion in selection and performance assessment.
Given Data / Assumptions:
Concept / Approach:
FAD is the volume flow rate of air delivered by the compressor, converted back to “free air” conditions (a defined standard temperature and pressure). It is not the raw volume at discharge conditions, nor simply “as is” volume. The correction uses the ideal gas relation to reference different operating sites and discharge pressures to a common basis.
Step-by-Step Solution:
Measure mass flow m_dot leaving the compressor.Convert to standardized volume: V_FAD_dot = m_dot * R * T_std / p_std.Report this standardized volumetric flow as FAD.
Verification / Alternative check:
Datasheets list SCFM or m^3/h (free air) at named reference conditions; on-site measurements require correction for local temperature and pressure.
Why Other Options Are Wrong:
Common Pitfalls:
Using discharge volumetric flow directly for comparison; always convert to the agreed standard state to compare machines.
Final Answer:
False
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