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View Full Version : Culverts in 2D models - ICM v6.5



Martin Spiers
January 20, 2016, 05:03 AM
We have a 2D mesh which includes a number of embankments. These have openings through them which would ideally be modelled as culverts with culvert entry/exit losses, however this doesn't work as the culvert outlet link requires another link downstream, and I want it to discharge back onto the 2D mesh.
The culverts are likley to be freely discharging in normal conditions but surcharged in large events.
Am I missing something or is there a better way of doing this?

Kristian Ravnkilde
January 25, 2016, 01:18 AM
2D outfalls linked by conduit. Or gully 2D at inlet.

Martin Spiers
January 25, 2016, 01:27 AM
2D outfalls linked by conduit. Or gully 2D at inlet.

Wouldn't that tend to under represent headloss at the entrance and exit?

Kristian Ravnkilde
January 25, 2016, 01:30 AM
Is that a great problem? May not be worth worrying about. You can set the Gully 2D curve to suit if it's a real issue. Or set a high headloss coefficient on the conduit.

Duncan Kitts
January 26, 2016, 02:00 AM
The calculations used to determine culvert inlet and outlet losses aren't applicable for use when coupling between the 1D and 2D domains. I, as Kristian suggests, would typically represent losses using the conduit headlosses.

If you have observed data on which to calibrate the headlosses to, you may want to consider representing the opening as a combination of a base linear structure and a sluice/bridge linear structure using the headloss field to represent losses. This way the opening is represented within the 2D domains rather than potentially introducing instabilities due to the 1D-2D coupling.