How do the power consumption and pressure output vary for a specific centrifugal air blower running at constant speed and capacity_______________?
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Answer: B. Directly as gas density
Explanation
Centrifugal blowers accelerate gas masses to generate dynamic pressure heads. Pressure output and power consumption depend directly on the mass of gas moved. Since volumetric capacity is constant, gas density scaling applies directly to power. Centrifugal blowers use rotating impellers to move large volumes of air or gases. Gas density varies with ambient temperature, pressure, and molecular composition. Fan laws relate rotational speed, flow capacity, pressure, and power consumption.
Ventilation systems operating at high altitudes must account for lower air density. Industrial gas compressors require power adjustments when switching to heavier process gases. Blower motor selection depends heavily on the density of the handled gas stream. Density squared scaling applies to rotational speed changes, not gas density variations. Square root scaling underestimates the direct linear impact of gas density on power. Inverse density scaling would incorrectly suggest lighter gases require more compressor power.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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