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Air Velocity Calculator
Calculate the air velocity inside a duct from the airflow and duct dimensions. Verify your duct velocities are within acceptable noise and pressure drop limits.
How to Calculate Air Velocity
Air Velocity (m/s) = Airflow (m³/h) ÷ (Area (m²) × 3600). For a rectangular duct, Area = Width × Height.
Monitoring air velocity is essential for noise control — velocities above 5 m/s in residential ducts can cause noticeable whistling and noise.
Frequently Asked Questions
What is a good air velocity in residential ducts?
2–5 m/s for main ducts, 2–3 m/s for branch ducts. Keep below 5 m/s to avoid noise issues.
How do I convert m/s to FPM?
Multiply m/s by 196.85 to get FPM (Feet per Minute). For example, 4 m/s = 787 FPM.
Air Velocity Calculator
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Airflow Calculator
Calculate airflow from duct area and air velocity.
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Convert Cubic Feet per Minute to cubic metres per hour.
L/s to m³/h Converter
Convert Litres per Second to cubic metres per hour.
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