Air Friction + Velocity Tool
Estimate duct area and air velocity from airflow (CFM) and round or rectangular duct dimensions. A quick field check for duct performance problems.
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Frequently asked questions
What does an air velocity tool calculate?
It calculates duct cross-sectional area and estimated air velocity in feet per minute (FPM) using airflow in CFM and duct size.
Why is duct air velocity important?
Duct air velocity affects noise, air distribution, comfort, and overall airflow behavior. Very high velocity can suggest undersized duct or restricted airflow.
Can this tool replace full duct design?
No. This tool is a practical field estimate. Final duct design should also consider friction rate, total effective length, fittings, static pressure, and full system layout.
Does this tool support round and rectangular ducts?
Yes. It supports both round and rectangular duct input so you can estimate area and velocity for common HVAC duct shapes.
Related calculators
- Static Pressure Budget Calculator
- Friction Rate Calculator
- Round ↔ Rectangular Duct Converter
- CFM from BTU / Tons Calculator
- ACH Calculator
- Delta T Calculator
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