Quick estimate of friction head loss per 100 m of straight pipe for a given flow and diameter - coarse engineering first-pass before Darcy-Weisbach refinement.
Formula
$$ h_f \approx 0.05 \cdot \frac{L}{D} \cdot \frac{v^2}{2g} \cdot 1.5 $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $v$ | Flow velocity | m/s | Q/A |
| $D$ | Inside diameter | m | pipe schedule |
Sources
- Perry’s Chemical Engineers’ Handbook.