Arch-pipe as Pond Outlet?

[Granny36]

Has anybody tried to model an arch pipe or anything other than the standard circular or rectagular as a culvert outlet? If so, I'd sure like to find out how you did it.

Thanks

 

[psmart]

If you open the culvert screen in HydroCAD and click the Help button you'll get some suggestions for modeling an arch pipe.

 

[TerryScan]

Granny:

As psmart points out, the help system suggests using the overall pipe dimensions with a 0.9 multiplier for arch pipe or 0.8 for eliptical pipe.

However, when I am dealing with finicky regulators, I use a "Special User Defined" outlet and supply data from HY-8.

 

[psmart]

A custom device will work fine - as long as you're not dealing with variable tailwater. But if the flow is tailwater-dependent, then you'll need to use one of the standard outlet devices, whose equations can handle the extra variable.