PVC pipe ā Darcy-Weisbach headloss
This page covers headloss calculation for PVC pipe using the Darcy-Weisbach equation ā the canonical pairing for Cold water, irrigation, sewer (gravity + pressure).
Pipe parameters ā PVC
- Hazen-Williams C-factor (new)
- 150
- Hazen-Williams C-factor (aged)
- 140
- Absolute roughness (Īµ)
- 5e-06 ft
- Typical uses
- Cold water, irrigation, sewer (gravity + pressure)
Darcy-Weisbach method
Universal ā works for any fluid + any flow regime (laminar, transitional, turbulent).
Formula
h_f = f Ā· (L/D) Ā· (VĀ² / 2g)Limitations
Requires the friction factor f, which depends on Reynolds number and relative roughness ā typically evaluated via the Colebrook equation or Moody chart.