How is the friction coefficient calculated in the formula for pipeline pressure drop?
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Formula for calculating pipeline pressure drop (Darcy-Weisbach equation): ΔP = f * (L/D) * (ρv²/2)； How is the friction coefficient f calculated in that case?
I searched online for the method of determining the friction coefficient f: for turbulent flow, the Colbrook formula is used; for iterative calculations, 1/f^0.5 = −2log(∈/D/3.7 + 2.51/Re/f^0.5), or the Moody Diagram can be referred to. Laminar flow (Re
"Formula for calculating pipeline pressure drop (Darcy-Weisbach equation): ΔP = f * (L/D) * (ρv²/2)； The friction coefficient f”; the friction coefficient (resistance coefficient) can be found in manuals or standards – relevant calculation formulas are provided in textbooks as well
Moditu is still the better choice. I took a look by myself and roughly understood how to do it.
It can also be found in the \"Power Piping Design Manual\". In Table 5-28 of Version 2, the friction resistance coefficient λ can be found; this corresponds to the friction coefficient f in the formula above.
Through computational methods: First, calculate the Reynolds number Re; if Re > 4000, the flow is turbulent. In this case, the friction coefficient λ can be determined using the formula “1/λ^0.5 = 1.74 – 2*lg(2*ε/d)”. Only the two parameters of absolute roughness ε and pipe diameter d are required.