You can find the function in SETUP/BASEMD/BASEPLANE_2D/GEOMETRY/MOVABLE_BED.

Best regards,
Lionel

This major release introduces several new features, model enhancements, and performance improvements. Key highlights include:

• The morphological acceleration factor (MORFAC) approach in BASEHPC for speeding up morphodynamic simulations

• Coriolis force momentum source term

• Massive extension and enhancement of the suspended load module in both BASEHPC and BASEchain (1D)

• The surface reconstruction method (SRM) combined with implicit frictional term treatment for solving hydrodynamic flux in extremely shallow conditions (e.g., surface run-off).

• Improved the performance of models with nodestrings and removed the limit of 200 nodes per nodestring

• New inner boundary type for BASEchain (1D) that computes discharge from a prescribed H-Q relation.

This version also includes extensive bug fixes, hence we recommend all users to update their program as well as the user manual to version 4.3. We kindly ask you to test your models with this version and give feedback if the program exhibits unexpected behavior. The changes compared to previous versions can be viewed at the following link: https://basement.ethz.ch/download/softw … -3-0.html/

The newest version of the software system BASEMENT is available as free download on our website https://basement.ethz.ch/

Kind regards
The development team of BASEMENT

We are pleased to announce the release of BASEmesh 2.3.1. This is a small bugfix release for the QGIS plugin:

• Fixed a crash when generating a quality mesh from a marker layer with empty (NULL) values in the MaxArea, MATID, or Hole fields.

Installation

The plugin is available in the BASEmesh plugin repository. Alternatively, you can download the archive from the release page and install it manually using the "Install from ZIP" option in the QGIS Plugin Manager. The Python package is available on PyPI:

pip install basemesh==2.3.1

Problems upgrading or uninstalling the plugin?

Upgrading, downgrading, or uninstalling the plugin from within QGIS can fail with the error messages "Plugin installation failed: Failed to unzip the plugin package" or "Plugin uninstall failed: Failed to remove the directory". This happens because QGIS keeps the plugin's compiled extension loaded while BASEmesh is enabled, so the plugin files cannot be replaced or removed. If you encounter this problem, please proceed as follows:

1. Open Plugins > Manage and Install Plugins > Installed and untick BASEmesh.

2. Close QGIS completely and start it again.

3. Upgrade, downgrade, or uninstall BASEmesh as usual.

4. If you uninstalled the plugin, re-enable it after reinstalling.

As a last resort, close QGIS and delete the basemesh_v2 folder in the python/plugins directory of your QGIS profile, then reinstall the plugin.

The full release notes are available on the release page. If you run into any other issues, please report them here in the forum.

Kind regards,
The BASEmesh development team

thank you again for your detailed explanation. This is very helpful.

Regarding the `minimum_water_depth`: in my current test model, I use 0.049 m because I start the simulation with an initial water depth of 5 mm in every cell. I had actually chosen 0.001 m initially, but with this value the program eventually stopped responding and got stuck, so for the current test I changed it to 0.049 m.

Regarding your hint about `geofile_Grid.err`: I cannot find this file in the Explorer directory of my simulation. It does not seem to be generated. Is there something I need to enable in order for this file to be written?

I have also tested `different CFL numbers´ in the meantime: 1.0, 0.95, 0.5 and 0.1. As expected, the number of mass conservation warnings decreases with decreasing CFL, as does the accumulated volume reported in these warnings. At the same time, the computational time increases, as does the total volume in the system. This seems plausible to me, since the numerical mass error is smaller with a lower CFL number.

I also tried to establish a `mass/volume balance´. I used two different approaches:

     1. I integrated the discharge time series using the trapezoidal rule. I integrated the rainfall input to obtain Q_in and the discharge at the downstream boundary to obtain Q_out. Based on this, I expected the remaining volume (water stored in the domain) to be:

          water stored in the domain = Q_in - Q_out - mass error.

     2. I also looked at the `balance.dat` file, which contains a volume value at the end of the simulation.

From my understanding, the volume at the final time in `balance.dat` should correspond to the remaining volume at the end of the simulation obtained from the first approach. However, the two values do not match for any of the CFL numbers I tested.

Interestingly, the difference between the two approaches becomes larger as the CFL number decreases.

Could you perhaps help me understand how the volume given in `balance.dat` is defined and how it relates to the integrated inflow/outflow and the mass conservation error? In particular, I would be very interested to know whether these two approaches should indeed result in the same volume.

Thank you very much again for your help and for taking the time to look into this.

Best regards,
Elli

You can do this by implementing a fixed bed. Have a look at Section 1.2.2.7 Bed Material and Fixed Bed Concept of the BASEHPC Reference Manual.

Best regards,
Matthias

I was not able to reproduce the error in the GUI on Ubuntu 22.04 with BASEMENT v4.2.0. Could you post a screenshot of the GUI with the error message?

What I find strange is that you see the STDOUT and STDERR tags in the GUI, those should not be displayed.

The BASEHPC specific executables (e.g. BMv4_BASEHPC_*) require the -f flag. Only the executables BMv4_setup, BMv4_simulation and BMv4_results require the input filenames as direct command line argumenets without any flags. Those can be used for both BASEHPC and BASEMD simulations.

Best regards,
Matthias

We are pleased to announce the release of BASEmesh version 2.3.0. You can install and upgrade to the new version directly using pip or ifyou use QGIS plugin, simply upgrade in plugin manager.

Key Changes:
- The new version performs large meshing and cleaning up drastically faster than before (~1 sec run time now for a previously ~1 hour task).
- Elevation looking up from a mesh is also much faster now (~12x faster)
- Fixed nodestring ordering for bent or zigzagging line strings, which could previously result in incorrectly ordered nodestrings.
- Breaking change for Python users: the deprecated basemesh.basechange import path is gone. Use import basechange instead.

For QGIS Plugin users:
- The progress bars now work normally and show what's happening;
- Fixed a bug where some valid elevation mesh layers didn't show up in the Advanced Interpolation tab;
- Linux builds of the plugin now include the same compiled speed-up as Windows.

Other changes:
- BASEchange: fixed the last cross-section of a CSV/tabulated channel not picking up the template's default values, unlike every other cross-section in the channel.

Kind regards
The development team of BASEMENT

Thanks for the specification. I think this is feasible and hopefully, we can include this in the next release.

Best regards,
Matthias

I'm having problems with my model using BASEHPC:

I'm facing the problem, that when modelling bridges and large culverts with h-Q relations (linked boundaries) i have big differences in the upstream and downstream water depth. This is to be expected with "no_momentum" but i also tried the other types.

While this wouldn't be as big of a problem for one linked boundary, in my model domain i have multiple in short succession occurring bridges/culverts, resulting in a really strange longitudinal water surface elevation profile along the river.

Regarding mesh quality: i have a really high resolution DEM, i implemented max_area of my cells at and around the boundary at 0.1 or 0.2. So this shouldn't be the problem.

For h-Q i used normal depth flow calculations, which are obviously quite sensitive to chosen slope and roughness value....

Is there a "BEST" approach to minimize or even eliminate these jumps in water depth/water surface elevation?

And what is the best way to implement h-Q relations when using BASEHPC? Like sort of a checklist on important things when creating the h-Q relations.

*EDIT:
In BASEMD there's the Gate boundary, why is this not implemented in BASEHPC?

Equilibrium transport capacity refers to the transport capacity calculated with the selected bedload formula type (e.g., MPM). What this actually does for the transport_capacity boundary condition in each time step:

1. Calculate the cumulative transport capacity Q_b over the boundary based on the transport capacity in each cell that borders that boundary
2. Calculate a specific transport capacity over the boundary by dividing by the nodestring length q_b = Q_b/L
3. Set the flux at each edge of the boundary to q_b

In this case, the hydraulic state just refers to the flow velocity and depth in the cells along the boundary.

For cases where the transport capacity varies strongly along the nodestring/boundary, this might result in deposition in cells along the boundary where the transport capacity is much smaller than the specific transport capacity q_b. If you want zero sediment transport over the upstream inflow boundary, you can simply not define a upstream boundary condition in the BEDLOAD block.

Best regards,
Matthias

This will be fixed in the next release! Thanks for the bug report.

Best,
Matthias

The elevation interpolation tool of BASEmesh allows to use multiple elevation sources, i.e. combination of DTM and elevation meshes. You could create a local elevation mesh in the regions where you want to overwrite the DTM elevation with other elevation information. Using lines and points directly is not possible at the moment.

Best regards,
Matthias

Thanks for the suggestion. I'll see if we can implement this.

Best regards,
Matthias

I guess you were able to answer this question in the meantime, but for future reference: This is typically done via the EXTERNAL_SOURCE block and using material indices, as you did in the model setup described here: https://forum.basement.ethz.ch/viewtopic.php?id=5590#1.

Best regards,
Matthias