Hector Montenegro Feflow-Anwender

Seeking for export of the 3D model structure along a cross section (boundaries and layering of the materials beneath the cross section) as a SHP (DXF, ascii-...)-file, so that the exported file may be used as a supermesh for the build up of a 2D-vertical plane model.

Such an export-feature was built in in FF5 and worked quite reasonable but it seems to be well hidden in FF7.2.

When trying to export a cross section, only the points of that particular line-element exported but not the desired structure of the cross section displayed.

If I understand you right you propose to assign a seepage boundary condition with a time variant constraint allowing so inflow during submersion for the specific nodes.
It sounds viable, at least in the case of simple  stage time series and a reasonable number of nodes. I will give a try!
Thank you very much for your support!

Hello Pete,

thank you for your hint!

I have not applied IFMs yet, so  am not familiar to these kind of external subroutines.
Is there already one suitable for fluctuating river stage boundary conditions?

The only one I found was:
[i]VaryingBC[/i]: Sets and removes boundary conditions and/or constraints for specific time intervals and node groups.

However in the required case the shift in BC must depend on the elevation of the respective nodes relative to the BC accounting for the external river stage.

Any further ideas?

Héctor

Hello Bastian,

thanks a lot for your help!
It turned out, that the troubles were generated by my graphic card driver. As Julia suggested I updated those (i.e. I downloaded the original Hewlett Packard drivers) and then I could reach the export menu without those strange crashes.

Have a nice day!

Héctor

Hello  outthere!

currently we are investigating the pressure propagation dynamics at embankments/dikes in the case of rapid river stage fluctuations.
I am uncertain how to apply the right boundary conditions at the slope surface (2D vertical plane model) in contact to the river.
Initially one can apply heads below the water surface and seepage above. When the river water table rises, then initially set "seepage-nodes" must change to "head-nodes" as soon as they are submerged. With river stage case "head-nodes" must change to "seepage-nodes" as soon as the river stage falls below the elevation of the respective nodes.
I presume that there must be a way to consider these river stage fluctuations via some kind of constraints.

Any clues warmly appreciated!

Héctor

Hello outthere!

Any clues how to export the slice-data trace view along an 2D or 3D line in FF6.1?
Any time I try to left click the slice-data trace window searching for a context menu offering export possibilities FF6.1 sort of crashes. To restore FF6.1 I have to  apply the win task-manager .

In FF5.4 it was simple to export, lets say  a file with x;h data, which could be loaded in any spread-sheet application in order to visualize/compare cross sections of potential at for different boundary conditions.

Any clues warmly appreciated

Héctor

Hello group,

a look at the manual FEFLOW Supermesh File Format (*.smh) - Version 5.4 reveals that the single superelements may not have any holes:

[i]Rules for polygonal superelements:

One polygonal superelement defines one polygon without any holes. The polygons are closed. The
endpoint of the polyline (that is identical with the startpoint) will not be stored and counted. For every
polygon border side a so called "midside node" will be stored to define curved and stretched border lines.
So in the geometry definition of a polygon the 1st, 3rd, 5th , ... node are polygon edge nodes and the
2nd, 4th, .. node are midside nodes. For polygonal superelements the number of nodes will always be even.[/i]

That is a pity! A subdivision of the polygon surrounding the "islands" might be a choice however this will introduce new element-edges- These might conflict with some line add-ins that must be considered in the course of mesh generation.

Héctor

Hello outthere,

I am trying to import a SHP-file as a basis for a superelementmesh generation. Within the domain there are a couple of zones like islands within the domain. When I import the SHP (created under ARCGIS) I have the "isles" as superelements but they lie below one superelement which corresponds to the outer boundaries of the "domain". In this way I am not able to specify the superelement "domain minus isles". The domain-polygon generate in GIS is not imported into FF as it should. It seems like some kind of "fill-inner-holes-procedure" manipulates the domain polygon.

However TRIANGLE generates a quit reasonable mesh.

Later I want to carry out some PEST work and I need a reasonable superelementmesh.

Any hints on the import of SHP are warmly appreciated!

Héctor

Hello outthere,

I would like to use PEST in a seepage-problem though a large concrete retaining wall where we have transient pore water pressure and temperature observations inside the structure. Until now we are familiar with the built in PEST2.0-option. This older PEST-version apparently does work only for "real" groundwater models .

Does PEST12.1 work for vertical plane unsaturated flow and transport problems?
Are there any example files, that would allow me to accommodate our model to the in-/out-put structure required by PEST?

Any hints warmly appreciated!

Héctor

Hello Forum,

Sometimes we have excavations or well borings and we want to analyse the ground's permeability/storage properties through observation of the temporal evolution of the recovery/refilling after dewatering of the excavation/boring.

I do not know how to represent this for the case of a 1,2 m diameter and 15 m deep boring which was pumped dry. Applying seepage face to the boundary nodes assumes a constant water level in the pit/well. In reality the seepage will lead to a water level rise in the boring and as consequence the outward gradients will be considerably reduced. In the above case we observed a rise of around 9 m in only 90 minutes.

To represent this process we needed a kind of loop in which the seepage volume at the end of a time step is converted into a water level change inside the pit/well. Applying a fine temporal discretization the solution should be straight forward.

Any clues how to manage this with FF?

Regards

Héctor