User Forum of Software BASEMENT

Loriann

User

Registered: 2023-07-05

Posts: 11

Culvert modelling in BASEMENT v4

Hello,

Is it possible to model culverts in BASEMENT ? In the river that I am modeling, at low discharges it is not really important that there is a culvert, but at high discharges the culvert loads and the flow becomes pressurized. Is it possible to model this at all in BASEMENT ? (I did not find anything about it in the documentation.)

Thanks

Matthias Bürgler

Developer

From: Zürich

Registered: 2019-04-04

Posts: 150

Re: Culvert modelling in BASEMENT v4

Hi Loriann

If you know the stage-discharge-relation of the culvert you can model it with a internal (or also linked if you use BASEHPC) hqrelation boundary condition.

Best Regards,
Matthias

Loriann

User

Registered: 2023-07-05

Posts: 11

Re: Culvert modelling in BASEMENT v4

Hi Matthias,

Thank you for your answer. I am using the BASEHPC and tried the linked boundary with hq-relation. I know that the culvert loads at Q=100 m3/s and that the height of the culvert "ceiling" is 375.7 m a.s.l, and I am modelling Q=110 m3/s. Therefore, I wrote the hq-relation file as follows :

372.4    0
375.7    100
375.7    110

Now I get a "mass balance problem", which I see from another post that it is common with linked boundaries starting from dry conditions, so I will follow this other post to try and solve the problem.

However, can BASEMENT actually handle the pressurized flow in the culvert ? (i.e. could there be a problem linked to the fact that I input the same wse for 2 different Q ?)

And second question :
what does the h exactly represent ? wse at the usptream linked boundary ? at the downstream one ? or the average on the entire culvert ?

Thanks

Last edited by Loriann (2023-08-10 09:15:52)

Matteo Facchini

Developer

From: Trento

Registered: 2014-09-05

Posts: 278

Re: Culvert modelling in BASEMENT v4

Hi Loriann
as far as I know there is no way to simulate pressurized flows in basement.
As for your second question: I think it is referred to the downstream string, since the upstream conditions are defined by the model.
Cheers
Matteo