Pipe Friction Loss Calculator

Pipe Parameters
m
Total length of the pipe
m
Inner diameter of the pipe
Material affects roughness coefficient
mm
Surface roughness height (ε)
Flow Parameters
m³/s
Volumetric flow rate (Q)
m/s
Calculated from flow rate and diameter
Fluid properties affect calculations
kg/m³
Mass per unit volume
Pa·s
Resistance to flow
°C
Affects fluid properties
Calculation Method
Recommended
Water only
Select calculation method
Roughness coefficient (C)
Calculated from Reynolds number and roughness
Results
Reynolds Number

0

Dimensionless
-
Friction Factor

0

Dimensionless
Head Loss

0

m
Pressure Drop

0

Pa
Graphs
Formulas
Darcy-Weisbach Equation

hf = f × (L/D) × (v²/2g)

Where:

  • hf = head loss due to friction (m)
  • f = Darcy friction factor (dimensionless)
  • L = length of pipe (m)
  • D = hydraulic diameter of pipe (m)
  • v = velocity of fluid (m/s)
  • g = acceleration due to gravity (9.81 m/s²)
Hazen-Williams Equation

hf = 10.67 × L × Q1.852 / (C1.852 × D4.8704)

Where:

  • hf = head loss due to friction (m)
  • L = length of pipe (m)
  • Q = volumetric flow rate (m³/s)
  • C = Hazen-Williams coefficient (dimensionless)
  • D = hydraulic diameter of pipe (m)
Reynolds Number

Re = (ρ × v × D) / μ

Where:

  • Re = Reynolds number (dimensionless)
  • ρ = density of fluid (kg/m³)
  • v = velocity of fluid (m/s)
  • D = hydraulic diameter of pipe (m)
  • μ = dynamic viscosity of fluid (Pa·s)