Darcy Weisbach equation (head loss form)

Input(s)

L: Length of the Pipe (m)

g: Acceleration due to Gravity $\left(\mathrm{m} / \mathrm{s}^{2}\right)$

V: Average Velocity of the Fluid Flow, Equal to the Volumetric Flow Rate per Unit Cross-sectional Wetted Area $(\mathrm{m} / \mathrm{s})$

D: Hydraulic Diameter of the Pipe (For a Pipe of Circular Section, this Equals the Internal Diameter of the Pipe) (m)

$f_{D}$: Dimensionless Coefficient Called the Darcy Friction Factor (dimensionless)

Output(s)

$\Delta \mathrm{h}$: Head Loss Due to Friction (m)

Formula(s)

$$ \Delta h=f_{D} * \frac{1}{2 * g} *\left(\frac{V^{2}}{D}\right) $$

Reference(s)

Wikipedia.org.