learn.howToCalculate
learn.whatIsHeading
Friction loss (pressure drop) in pipes and ducts represents energy loss. It's critical for pump and fan sizing.
Formule
Hazen-Williams: hf = (10.67×L×Q^1.85) / (C^1.85×D^4.87)
- L
- L value — Variable used in the calculation
- Q
- Q value — Variable used in the calculation
- C
- C value — Variable used in the calculation
- D
- D value — Variable used in the calculation
Guide étape par étape
- 1Hazen-Williams: hf = (10.67×L×Q^1.85) / (C^1.85×D^4.87)
- 2Darcy-Weisbach: hf = f×(L/D)×(V²/2g)
- 3Results show required head or fan power
Exemples résolus
Entrée
PVC pipe (C=150), Q=0.05 m³/s, D=50 mm, L=100 m
Résultat
hf ≈ 10-12 m head loss
Significant energy requirement
Erreurs courantes à éviter
- ✕Neglecting minor losses (fittings, valves)
- ✕Using wrong friction coefficients for pipe age
Questions fréquentes
How does diameter affect friction loss?
Loss inversely proportional to D^5 (or D^4.87); doubling diameter reduces loss 32×.
What is dynamic viscosity's role?
At low Reynolds numbers (laminar), viscosity dominates friction. At high (turbulent), roughness dominates.
Prêt à calculer ? Essayez la calculatrice gratuite Friction Loss
Essayez-le vous-même →