Conduits flow and mean velocity - the Chezy equation
The Chezy equation can be used to calculate mean flow velocity in conduits:
v = c (R S)1/2 (1)
v = mean velocity (m/s, ft/s)
c = Chezy roughness and conduit coefficient
R = hydraulic radius of the conduit (m, ft)
S = slope of the conduit (m/m, ft/ft)
ε is the characteristic height of the roughness elements on the channel boundary.