User Forum of Software BASEMENT

Stm

User

Registered: 2024-01-26

Posts: 1

Model outflow sink vs. stringdef

We have conducted some test simulations (some with, some without precipitation) with BASEMENT v4 where we tried to evaluate the influence of different methods to remove water from a simulation. The “regular” way seems to create a StringDefinition i.e. uniform_out. However, especially with precipitation activated, we found “sinks” to work very well. We created a narrow area of elements around the initial model boundary and then defined it as a sink (sinks as elements with an assigned low elevation). It abstracts water if it leaves the area of interest. The model boundary needs to be set with care, as water cannot re-enter at the sides. We also found this method to be working fine with larger flows (i. e. rivers with flows > 100 m³/s) and it seems to be a little easier to implement, as no slope needs to be set . We could not find significant differences in the results, the WSE and velocity only differs marginally. So far the only downside we found is that if the “boundary sink” is assigned a single MatID, the outflow cannot be monitored quantitatively. This leads us to our question:

Are there significant (technical) drawbacks of using sinks over string definitions (i. e. uniform out) to abduct water from the model other than “missing” the possibility of a measured output?