EngineeringToolkit

Darcy-Weisbach Equation (Fluid Mechanics) Formula

Relates the pressure loss due to friction along a pipe to the average velocity of the fluid flow.

Formula

Δp = f × (L/D) × (ρv²/2)

Discipline: Fluid Mechanics. Result unit: Pa.

Variables and units

  • Δp — Pressure Loss (Pa): Pressure loss
  • f — Friction Factor: Darcy friction factor
  • L — Length (m): Pipe length
  • ρ — Density (kg/m³): Fluid density
  • v — Velocity (m/s): Flow velocity
  • D — Diameter (m): Pipe diameter