Output
Channel Discharge Q=1.49⁄n Aw R
h2⁄3 So½
= 1.49⁄ (
)()
2⁄3()½
= cfs
Channel Flow Velocity V = Q⁄Aw
= ⁄
= ft/s
Freeboard Fb =
1⁄6(d + V2⁄(2(g)))
= 1⁄6( + 2⁄(2())) =
Top Width TW = LB + RB + W
= + + = ft
Manning Equation Variables
Wetted Area of Flow
A
w=(d)(LB)(½) + (d)(RB)(½) + (W)(d)
= ()()(½) + ()()(½) + ()()
= ft2
Wetted Perimeter Pw= RBP + LBP + W
= ft +
ft +
ft
= ft
Hydraulic Radius Rh=Aw⁄
Pw=
ft
2 ⁄
ft
= ft
Channel Geometry Variables
Left Bank Width LB = (d)(Left Bank Slope)
= ()() = ft
Right Bank Width RB = (d)(Right Bank Slope)
= ()() = ft
Right bank perimeter length
RBP = √( RB2 + d2 ) = √(2+
2) = ft
Left bank perimeter length
LBP = √( LB2 + d2 ) = √(2+
2) = ft