Empirical equation, which relates pressure loss \displaystyle \frac{dp}{dl} along pipeline (also called head loss), due to fluid friction with pipelines walls along the pipe trajectory to the average cross-sectional velocity u of the fluid flow:
| (1) | \frac{dp}{dl} = - f \cdot \frac{ \rho \, u^2 \, }{2 d} |
where
f | Darcy friction factor |
\rho | fluid density |
d | pipe diameter |
See also
Physics / Fluid Dynamics / Pipe Flow Dynamics / Fluid friction with pipelines walls