User Forum of Software BASEMENT

Manuel

User

From: 3800 Interlaken, BE

Registered: 2021-05-07

Posts: 2

Problem with discharge from StringDef

There is a unexpected behaviour of the standard boundary condition of the type "uniform_in" and "froud_in". The discharge from file or direct input (item "discharge" or "discharge_file") works only for one upstream direction. The input is generated for the upstream direction "right" but not for the direction "left". Unfortunately in my case,  the defined upstream direction "right" points upwards (against the slope). For the correct definition of the upstream direction (which should be "left") no inflow is generated - the simulation ends within seconds.
I tried the invert the point number along the StringDef in the the mesh file but the problem remains. The inflow is generated only for the uphill direction.
Is there a way to fix this problem? I use Version 3.1.1 / March 2021.

I put an example on:
https://www.swisstransfer.com/d/8163b2f … eeda87d86b

The simulation runs without problems if you simply change the upstream direction from "left" to "right" for the STRINGDEF "inflow1" from "left" to "right".

Matthias Bürgler

Developer

From: Zürich

Registered: 2019-04-04

Posts: 150

Re: Problem with discharge from StringDef

Hi Manuel

The standard inflow boundaries such as froude_in or uniform_in are intended to be use on actual mesh boundaries. Using those boundaries inside the mesh (as an internal boundary) can result in unexpected behavior and there is no logic defined for this case (e.g. what happens with water hitting such a boundary from on of the sides). The only workaround that I can think of right now, is to cut out a thin hole in the mesh, where you want to place the boundary.

Best regards
Matthias

Manuel

User

From: 3800 Interlaken, BE

Registered: 2021-05-07

Posts: 2

Re: Problem with discharge from StringDef

Hi Matthias

Thank you for the informations. The workaround works fine in this case.