MAXScanner thermal & fluid engineering
Darcy-Weisbach Calculator — Pipe Head Loss & Pressure Drop
Calculate pipe friction head loss and pressure drop from Darcy friction factor, length, diameter, velocity and density.
Last updated: September 17, 2026
Results
Enter valid non-negative flow inputs and positive diameter/density
Formula, example and assumptions
h_f=f(L/D)v²/(2g); ΔP=ρgh_f.
f=0.02, L=100 m, D=0.1 m and v=2 m/s gives about 40.8 m head loss.
- The entered factor is the Darcy, not Fanning, friction factor.
- This owner models straight-pipe major loss; fittings require separate minor-loss terms.
Frequently asked questions
What is Darcy-Weisbach used for?
It estimates major friction loss in fully developed internal pipe flow.
How do I get friction factor?
Use the existing Darcy friction-factor owner with Reynolds number and relative roughness.