Inputs
m³/s
m
m (boxes only)
m
m/m
RC ≈ 0.013, CMP ≈ 0.024
0.2 groove HW, 0.5 sq HW, 0.9 proj
m above outlet invert
Method & assumptions
- Inlet control (HDS-5 Eq. A.6): HW/D = c·(Q/(A·D0.5·g0.5))2 + Y − 0.5·S0 for unsubmerged, or capped at submerged form.
- Outlet control: HW = TW + hL − S0·L; hL = (1 + ke + 2g·n²·L/R4/3)·V²/(2g).
- HW = max(HWinlet, HWoutlet) = controlling.
- Coefficients used: HDS-5 Chart 8 (Concrete pipe square), Chart 1 (CMP), Chart 16 (Concrete box).
- Simplified — does not handle outlet velocity dissipation, trash, or submerged tailwater jump.
Results
Area A—
Velocity V (full flow)—
Hydraulic Radius R—
Inlet HW (HW/D)—
Outlet HW—
Controlling HW—
Control Type—