Channel Flow Calculation - Mannings equation
v = 1/n x R
2/3
x S
1/2
Where :
n =
coefficient of roughness
(typically 0.3)
v = Water velocity down the channel (m / sec) = flow (m
3
sec
-1
) / cross sectional area (m
2
)
R = Hydraulic radius (m) = cross sectional area (m
2
) /
wetted perimeter
(m)
S = Gradient of channel (m / 100m)
