Manning Flow Velocity is an empirical formula for open channel flow, or flow driven by gravity. Here we can calculate for Flow Velocity, Hydraulic Radius, Energy Grade Line Slope, Roughness Coefficient.
Manning Flow Velocity is an empirical formula for open channel flow, or flow driven by gravity. Here we can calculate for Flow Velocity, Hydraulic Radius, Energy Grade Line Slope, Roughness Coefficient.
Hydraulic Radius: 
Energy Grade Line Slope: 
Roughness Coefficient: 
where,
V = Flow Velocity,
R = Hydraulic Radius,
S = Energy Grade Line Slope,
n = Roughness Coefficient.
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