Open Channel

Open channel hydraulic radius, wetted perimeter, area



Select open channel: 
Depth, y (L): 
© 2014 LMNO Engineering, Bottom Width, b (L): 
Research, and Software, Ltd. Side Slope, z (H:V): Area, A (L2): 
Wetted Perimeter, P (L): 
Hydraulic Radius, R (L): 
Top Width, T (L): 

Open channel units: Any units in the open channel calculator may be used, so long as they are consistent. (L) means that the variable has units of length (e.g. meters). (L2) means that the variable has units of length squared (e.g. m2) in the open channel calculator.

Open Channel Diagram and Equations:

Open Channel Cross-Sections

In open channel, z is side slope of trapezoidal and triangular channels, defined as horizontal to vertical ratio. Both sides of the open channel are assumed to have the same side slope.

Open Channel Equations (note that R=A/P):
Open Channel Equations

The non-circular open channel geometry calculation does not check for unreasonable inputs. Please enter positive values.


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