Calculate Darcy and Fanning friction factors using Colebrook-White, Swamee-Jain, and Churchill correlations. Visualize results on an interactive Moody diagram.
Commercial steel = 0.0018 in
For ΔP calculation
Understand friction factor correlations, Moody diagram interpretation, and flow regime identification
This calculator computes Darcy and Fanning friction factors using three methods: Colebrook-White iteration (industry standard), Swamee-Jain explicit approximation, and Churchill correlation. It also generates an interactive Moody diagram.
The Darcy friction factor is four times the Fanning friction factor (f_Darcy = 4 Γ f_Fanning). Darcy is more common in pipeline engineering while Fanning is used in chemical engineering. This calculator reports both values.
Commercial steel and wrought iron pipe has an absolute roughness of 0.0018 inches (0.046 mm). Other common values include galvanized iron at 0.006 in, cast iron at 0.010 in, and PVC/plastic at 0.00006 in.
Laminar flow occurs at Re < 2,100 where f = 64/Re. The transition zone is 2,100 < Re < 4,000 and is unstable. Turbulent flow occurs at Re > 4,000, where the Colebrook-White equation applies.