Fan Efficiency

Fan efficiency should be judged wire-to-air — from electrical input to useful air power — not from motor nameplate alone. Articles cover FEI metrics, part-load behaviour, annual energy calculation and the design factors separating premium EC platforms from commodity fans.

Backward-Curved vs Forward-Curved Impeller — What's Inside
By longwell / September 21, 2026 / Fan Engineering Guides

Backward-Curved vs Forward-Curved Impeller — What’s Inside

Forward-curved and backward-curved centrifugal fans can share a diamet...

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Impeller Blade Types Compared (Radial/FC/BC/Airfoil)
By longwell / September 20, 2026 / Fan Engineering Guides

Impeller Blade Types Compared (Radial/FC/BC/Airfoil)

How do radial, forward-curved, backward-curved and airfoil centrifugal...

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What Is Fan Efficiency (FEI) and Why It Matters
By longwell / September 20, 2026 / Fan Engineering Guides

What Is Fan Efficiency (FEI) and Why It Matters

An FEI of 1.25 does not mean 125% efficiency. This engineering walkthr...

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Forward-curved and backward-curved centrifugal wheels ready for selection
By longwell / September 20, 2026 / Fan Engineering Guides

Backward-Curved vs Forward-Curved: Which to Choose

Both wheels turn in a scroll and both move air outward, yet they suit ...

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Backward-Curved Fan Noise: A Same-Duty Comparison Guide
By longwell / September 18, 2026 / Fan Engineering Guides

Backward-Curved Fan Noise: A Same-Duty Comparison Guide

Why can a backward-curved centrifugal fan run quieter at the same airf...

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How to Read a Fan Performance Curve to Pick a Fan
By longwell / September 18, 2026 / Fan Engineering Guides

How to Read a Fan Performance Curve to Pick a Fan

How do you use a fan performance curve to select the right fan? This e...

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Fan Motor Sizing: HP, Voltage & Full Load Amps
By longwell / September 18, 2026 / Fan Engineering Guides

Fan Motor Sizing: HP, Voltage & Full Load Amps

Size a fan motor from the real duty point—not from CFM alone. This wor...

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Grid of small fans beside a single large centrifugal fan for comparison
By longwell / September 13, 2026 / Fan Engineering Guides

Grid of Small Fans vs One Big Fan: Efficiency Truth

Arrays are often sold as more efficient than a single large fan. On pu...

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Fan test chamber set up for AMCA 210 airflow measurement
By longwell / September 13, 2026 / Fan Engineering Guides

How We Test Fans (AMCA 210/211 Method)

A fan curve only means something when you know how it was produced. Th...

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Axial fan blade pitch and angle of attack shown on a hub
By longwell / September 10, 2026 / Fan Engineering Guides

Fan Blade Pitch & Angle of Attack Explained

Pitch is the single strongest lever on axial fan performance. Increase...

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