Good morning,
Does anyone know how exactly these two fields "Is Overflowing?" and "Is Ever Overflowing?" affect the results of max depth (ft) and Max Hydraulic Grade (ft)?
In general, wherever I have the "Is Overflowing?" box unchecked I see a much greater Max Hydraulic Grade compared to Max Depth. Any thoughts on this?
Thank you in advance,
Samir
Hello Samir,
Samir Farra said:In general, wherever I have the "Is Overflowing?" box unchecked I see a much greater Max Hydraulic Grade compared to Max Depth. Any thoughts on this?
This could be because you might be using "bolted" manholes which can show the hydraulic grade above the manhole rim elevation without overflow (the "is overflowing?" field is set to "False"). If you are not using a bolted manhole this could be related to tailwater. Sometimes the Implicit solver (if you are using it) ignores overflow in favor of stability. See this article which explains this phenomenon and how to remedy it: Zero overflow at manhole despite HGL above rim.
Additionally see this article which explains what happens when a node is "surcharged" or "overflowing": Difference between a "surcharged" and an "overflowing" node
Hope this helps.
Regards,
Yashodhan Joshi