EngiRef / Civil Engineering Formula
Manning's Equation
Manning's Equation: Velocity in open channel flow. A Hydraulics formula in civil engineering. Variables V, n, R and S, each with SI and imperial units.
Hydraulics
Specification
- Name
- Manning's Equation
- Discipline
- civil
- Category
- Hydraulics
- LaTeX
- V = \frac{1}{n}R^{2/3}S^{1/2}
- Description
- Velocity in open channel flow
- Conditions
- SI units, uniform flow in open channels
- Can solve for
- V, n, R, S
- Tags
- manning, open channel, flow, velocity
Variables
| Symbol | Name | Unit | Si Unit | Imperial Unit |
|---|---|---|---|---|
| V | Velocity | m/s | m/s | ft/s |
| n | Manning's n | - | - | - |
| R | Hydraulic Radius | m | m | ft |
| S | Channel Slope | - | - | - |
Common questions
- What is the Manning's Equation formula?
- Velocity in open channel flow. It sits under Hydraulics, Civil engineering in the EngiRef reference.
- What do the symbols in the Manning's Equation formula mean?
- In Manning's Equation, V is velocity in m/s; n is manning's n; R is hydraulic radius in m; S is channel slope.
- When does the Manning's Equation formula apply?
- Manning's Equation holds under this condition: SI units, uniform flow in open channels.