Air Flow Calculator
Calculate air flow (CFM), air velocity, duct sizing, and pressure drop for HVAC systems, ventilation, and industrial applications.
Step 1: Duct & System Details
Understanding Air Flow
Air flow (CFM) is calculated by multiplying duct cross-sectional area by air velocity. Proper duct sizing ensures efficient airflow with minimal pressure drop and noise.
Step 2: Air Properties & Conditions
About Air Flow Calculations
CFM (Cubic Feet per Minute) is the standard measurement for air flow. Proper air flow ensures adequate ventilation, temperature control, and system efficiency in HVAC applications.
Air Flow Calculation Results
Calculated Air Flow Rate
Duct Size Air Flow Comparison
| Duct Size | Area | Air Flow (CFM) | Velocity (FPM) | Pressure Drop |
|---|
Air Velocity Profile
Air Flow Calculation Formula
CFM = Area (ft²) × Velocity (FPM)
For circular ducts: Area = π × (Diameter/2)². For rectangular ducts: Area = Width × Height. All dimensions must be converted to feet for CFM calculation in imperial units.
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