Calculate pressure drop or head loss in a pipe due to friction.
Pipe & Flow Parameters
m
m
m/s
kg/m³
Calculation Results
Enter parameters to calculate
About this calculator
Quick Reference
h_fHead Loss
fDarcy Friction Factor
LPipe Length
DPipe Diameter
vFlow Velocity
gGravity (9.81 m/s²)
Overview
The Darcy-Weisbach equation is an empirical equation that relates the head loss, or pressure loss, due to friction along a given length of pipe to the average velocity of the fluid flow for an incompressible fluid.
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Pro Tips
The friction factor (f) is usually determined from the Moody diagram or the Colebrook-White equation.
For laminar flow (Re < 2300), f = 64 / Re.
Ensure all units are consistent (SI units are recommended).
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Fun Facts
"The equation is named after Henry Darcy and Julius Weisbach, who independently contributed to its development in the mid-19th century."
"It is considered the most accurate model for calculating friction loss in pipe flow."
