onlinechannel15.php:   Discharge in a prismatic channel using the Manning equation

Definition sketch for a prismatic channel
Formulas:

P = b + 2y(1 + z2)1/2
T = b + 2zy
A = y(b + zy)
R = A/P
D = A/T
Q = (C/n) AR2/3S1/2
V = Q/A
F = V/(gD)1/2
INPUT DATA:

Select:   

Bottom width b:  

Flow depth y:  

Side slope z:  

Manning's n:  

Bottom slope S:  

INTERMEDIATE CALCS:

Units selected:   

Gravitational acceleration g:   

Constant C:   

Wetted perimeter P:   

Top width T:   

Flow area A:   

Hydraulic radius R:   

Hydraulic depth D:   

OUTPUT:

Discharge Q:   

Flow velocity V:   

Froude number F:   

            

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