Calcolatrice Equazione di Manning — Formula
## Manning's Equation for Open Channels
The Manning equation is the most widely used formula for computing uniform open-channel flow.
### Formula
**V = (1/n) R^(2/3) S^(1/2)**
**Q = A V**
where n is Manning's roughness coefficient, R is the hydraulic radius (A/P, area divided by wetted perimeter), and S is the slope of the energy grade line (equal to channel slope for uniform flow).
The Manning equation is the most widely used formula for computing uniform open-channel flow.
### Formula
**V = (1/n) R^(2/3) S^(1/2)**
**Q = A V**
where n is Manning's roughness coefficient, R is the hydraulic radius (A/P, area divided by wetted perimeter), and S is the slope of the energy grade line (equal to channel slope for uniform flow).
Esempio Risolto
A concrete-lined channel with n=0.013, R=0.5 m, slope 0.2%, area 1.5 m^2.
- R^(2/3) = 0.5^0.667 = 0.630
- S^(1/2) = 0.002^0.5 = 0.04472
- V = (1/0.013) x 0.630 x 0.04472 = 76.92 x 0.02817 = 2.168 m/s
- Q = 1.5 x 2.168 = 3.252 m^3/s