This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Riser/culvert control structure

Original forum thread: https://communities.bentley.com/products/hydraulics___hydrology/f/haestad-hydraulics-and-hydrology-forum/180556/pondpack-maximum-water-surface-elevations-issue---2yr-10yr-and-100yr-at-pond-bottom

?Yes, that did the trick. On another note, the pond outlet control structure includes a Riser structure with weir + orifice opening, and two(2) pipes existing the riser. How would that be modeled in pondpack

Parents
  • Hello Ekene, 

    The riser control structure includes input for weir and orifice data. If the riser drains to a culvert, you would include the culvert in the composite outlet structure and set the riser's Downstream ID to be the culvert. If the culvert has two barrels as implied above, you can set this in the culvert properties. You can also set the dimensions of the culvert to be an equivalent size.

    Regards,

    Scott

Reply
  • Hello Ekene, 

    The riser control structure includes input for weir and orifice data. If the riser drains to a culvert, you would include the culvert in the composite outlet structure and set the riser's Downstream ID to be the culvert. If the culvert has two barrels as implied above, you can set this in the culvert properties. You can also set the dimensions of the culvert to be an equivalent size.

    Regards,

    Scott

Children
  • Note that I split this into a new thread, since this is a new issue.

    Regards,

    Scott

  • To add to Scott's answer - 

    If the 2-barrel culvert leaving the structure has more capacity than the riser+orifices, you might consider omitting them from the composite outlet structure to avoid convergence issues described in the following article from our Wiki: Convergence problems, very slow calculations or "out of range" message when using culvert in series with another outlet component

    If the culverts have less capacity and might influence the hydraulics of the riser and orifices, and if they have different sizes, you could choose an average for the diameter in the composite outlet structure, with the number of barrels set to two (or a diameter that is hydraulically equivalent to the performance of the two together).

    If the two culverts have different inverts and you cannot approximate a single invert elevation (since the riser and orifice can only have a single downstream ID), or if they discharge to two separate locations, then you would need to model the inside of the riser as a separate pond (consider using the "no volume" option for the Volume Type property) with a separate composite outlet structure leaving that "pond", with two separate convert components at different inverts. Or in the case of the culverts discharging to separate places, you would use two separate outlet node and link elements, with separate composite outlet structures, each with their own respective culvert component.

    If the orifices are on the side of the riser, make sure you set the "Downstream ID" of the orifices to the next-downstream element (the 2-barrel culvert, or "tailwater" if omitting the culverts) See more about riser+orifice here.


    Regards,

    Jesse Dringoli
    Technical Support Manager, OpenFlows
    Bentley Communities Site Administrator
    Bentley Systems, Inc.