Spillway Designxls Install | Ogee
For a vertical upstream face, the spreadsheet uses the following coordinates:
) passing over the ogee crest is calculated using the standard weir equation:
The primary volumetric capacity of an uncontrolled ogee spillway is governed by the specialized weir flow formula: ogee spillway designxls install
Ensure the curve is smooth; any "steps" in the graph suggest an error in the input parameters or a broken formula in the coordinate columns.
Ensure that the pressures along the profile remain positive to prevent catastrophic cavitation damage. For a vertical upstream face, the spreadsheet uses
Generates precise coordinates in seconds compared to hours of manual calculations.
Account for contractions caused by bridge piers and lateral abutments using the formula: Account for contractions caused by bridge piers and
Many textbooks state that the effect is negligible when P/Hₑ > 1.33. However, if the dam is low or the reservoir is wide, Vₐ²/(2g) can be significant.
where:
An ogee spillway design template is incomplete without a visual profile graph. Follow these steps to generate a geometric plot: Highlight your calculated coordinate columns. Insert an .
The engineering template is organized into three foundational tabs: Required Inputs Generated Outputs Design discharge ( ), Crest height ( ), Spillway width ( ), Pier count Effective crest length ( Lecap L sub e ), Design head ( Hdcap H sub d ), Discharge coefficient ( 2. Profile Generator Step intervals ( ), Upstream face slope ratio Coordinates coordinates , S-curve curvature plot, Tangent point matching 3. Cavitation Check Maximum operating head ( Hmaxcap H sub m a x end-sub ), Atmospheric pressure Pressure distribution envelope, Cavitation index ( ), Risk assessment flag 4. Visualizing the Ogee Crest Profile