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Moody Chart Friction Factor from Reynolds Number and Roughness Calculator

Colebrook–White equation for Darcy friction factor.

Approximates the Darcy–Weisbach friction factor using the Colebrook–White equation (Churchill approximation): 1/√f = −2·log₁₀(ε/(3.7D) + 2.51/(Re·√f)).

Daniel Oh By Daniel Oh
Published Last reviewed 1 min read

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Formula

1/√f = −2 log₁₀[ε/(3.7D) + 2.51/(Re√f)]

In depth

Approximates the Darcy–Weisbach friction factor using the Colebrook–White equation (Churchill approximation): 1/√f = −2·log₁₀(ε/(3.7D) + 2.51/(Re·√f)).