Hydraulic Radius of a Triangular Channel

Hydraulic radius, abbreviated as \(r_h\), is the area cross-section of water in a pipe or channel divided by the wetting perimeter.

 

Hydraulic Radius of a Triangular Channel formulas

\(\large{ r_h =  \frac  {  A_c }  { P_w }   }\)
\(\large{ r_h =  \frac  {  z\;h^2 }  { 2\;h \; \sqrt  {1  \;+\;  z^2 } }   }\)

Where:

Units	English	Metric
\(\large{ r_h }\) = hydraulic radius	\(\large{ft}\)	\(\large{m}\)
\(\large{ A_c }\) = area cross-section of flow	\(\large{ft^2}\)	\(\large{m^2}\)
\(\large{ b }\) = bottom width of fluid	\(\large{ft}\)	\(\large{m}\)
\(\large{ h }\) = depth of fluid	\(\large{ft}\)	\(\large{m}\)
\(\large{ w }\) = top width of fluid	\(\large{ft}\)	\(\large{m}\)
\(\large{ P_w }\) = wetting perimeter	\(\large{ft}\)	\(\large{m}\)
\(\large{ z }\) = width of channel slope	\(\large{ft}\)	\(\large{m}\)