Flow into flared pipe

[workingweekends]

Vertical pipe with flared end is used as a glory hole to return the supernatant of a pond to disinfection. Need to accurately determine the flow per height above the crest to establish the ponds capacity for attenuation.

I feel tempted to use the broad crested weir equation and call it a day but its more like a micro spillway. Not sure what equation to use.

Ideas? References?

 

[LittleInch]

Try this?

https://www.usbr.gov/tsc/techreferences/designstandards-datacollectionguides/finalds-pdfs/DS14-3.pdf

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[workingweekends]

They report C value for ogee crest as 3.7, got it! Thanks!