Open Channel
Manning's Open Channel Flow
Steady uniform flow in an open channel. Select a section shape and the calculator computes hydraulic radius, velocity, and discharge.
Formula
V = (1/n) · R^(2/3) · S^(1/2), Q = A · V
Geometry
Use the inputs that match your selected shape.
Resultlive
- Area, A
- 0.6m²
- Wetted perimeter, P
- 2.2m
- Hydraulic radius, R
- 0.27273m
- Velocity, V
- 1.023m/s
- Discharge, Q
- 0.6138m³/s
- Discharge, Q (L/s)
- 613.8L/s
Reference: Manning's equation (SI units). For circular pipe flowing partially full, use a depth-ratio chart or solve geometrically.