EngineeringToolkit

Manning's Equation (Hydraulics) Formula

Calculates the velocity of water flow in open channels and pipes.

Formula

V = (1/n) × R^(2/3) × S^(1/2)

Discipline: Hydraulics. Result unit: m/s.

Variables and units

  • V — Velocity (m/s): Average velocity of flow
  • n — Manning's Coefficient: Manning's roughness coefficient
  • R — Hydraulic Radius (m): Hydraulic radius
  • S — Slope: Channel slope