Inputs
Enter duct geometry and at least one parameter.
Results
Calculated from the current geometry and operating inputs.
- Hydraulic diameter
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- Duct area
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- Darcy friction factor
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- Solve path
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Solve velocity, flow, or pressure drop for round and rectangular ducts using Darcy-Weisbach.
Enter duct geometry and at least one parameter.
Calculated from the current geometry and operating inputs.
Pressure drop is computed over 100' using Darcy-Weisbach with a laminar branch and a Colebrook friction factor for galvanized steel in transitional and turbulent flow.
Hydraulic diameter Dh = 2WH / (W + H).
Standard air at ~70 °F with density 1.204 kg/m³, viscosity 1.81×10⁻⁵ Pa·s, and galvanized steel roughness of 0.15 mm.
Generate a sizing table for a given airflow. Set a target to highlight the best fit with a heat map.
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