Modeling Open Channels in Hydraflow

[MrNYPE]

Using the standalone versions of Hydraflow Express, Stormsewers, Hydrogragphs. Also had easy access to the Civil 3D extensions, but haven't used them yet.

Trapezoidal channel, and the cross-section stays the same for the length of the channel. Due to site restrictions, the alignment cannot be modified much- one edge sits on the property line, tying into the existing contours. The other end is adjacent to a soil buttress that is part of a slope stabilization. The channel slope varies along the flow path of the channel.

I thought there was some way to model this uniform geometry trapezoidal channel with changing bottom slope in Hydraflow. I need to determine velocity, freeboard, and hydraulic jump locations to complete my design and prepare the design report.

Any thoughts on how to do this?

Thanks in advance.

 

[RWF7437]

Suggest you use HEC-RAS. It's free, and for this simple problem, would be as easy to learn and use ad Hydraflow. Hydraflow, by the way, is no longer available or supported except by Autodesk.

good luck

 

[RWF7437]

Probably of more importance is the question: where did you get your design flows ? If they are based on any of the available hydrology methods they are likely to be no more reliable than 30% to 50%. Even greater errors of estimate are common.

good luck

 

[MrNYPE]

HEC-RAS. I can't believe I didn't think of that- I've only been using it for 6 years.

Thanks for your help.

I know that Hydraflow is not longer available as a standalone. Since their website is gone, I don't have access to their user forums anymore.

The design flows have to be generated using the Rational Method- it's the city code. Fairly inaccurate, but it's what is required, so I've built in a bunch of safety.

 

[RWF7437]

Have you considered regional regression equations ??

 

[RWF7437]

http://pubs.usgs.gov/sir/2006/5112/