Alexander Renz

If exclusively working with the 3D layer configurator, the way you have described is the designated and also the most effective one. An alternative is to apply elevation data from external files (that would also include the top/bottom elevation of your well) by using regionalization methods.

Well boundary conditions cannot be set between layers. However, there is often no reason to do so (except for local scale models), provided that the well is located in the correct geological unit (aquifer). Significant differences in the computational results of models with different depths of the well bore are typically restricted to the area very close to the well.  Wide-range effects are usually negligible.

Hi,

FEFLOW looks for the plug-in in the directory from where FEFLOW is started (the directory that is shown in the command shell).
The safe way is to specify the file by an absolute path. The filename must contain the extension (e.g., "C:\Program Files\WASY\FEFLOW 6.0\modules64\myplugin.dll")

best regards,
Alex

Hello Badoux,

Yes, MS Visual C++ 2010 Express Edition is compatible with the IFM Interface and can be used to create Plug-Ins for FEFLOW.

regards,
Alex

Hi,
The best way to import initial conditions is to use inverse distance weighting with only one neighbour (5.x / Classic Interface) or to use the neighboorhood relationship (in FEFLOW 6.0 Standard Interface).
It is hard to say why you do actually not see any data. Is this a 3D model? Do you import the data slice by slice?

The way FEFLOW handles dry cells depents on the model type: In unsaturated mode, the capillary relationships are taken into account to model the capillary updraft in this area. In saturated/unconfined/free+movable mode, the top slice is shifted after each time-step to match the water table. In saturated/unconfined/phreatic mode, the conductivity of a dry cell is set to a very small value (a semi-saturated cells conductivity is scaled linearly with the saturation).

Which model to choose depends on the actual model details; however from your description I would guess that the saturated/phreatic mode would be appropriate. It is important to set the right settings here (3D model): in the free+surfaces editor, open "constraints" and set the "touching the top surface" to unconstrained". In the "specific options" dialog, choose "confined". In this way, FEFLOW will handle the top surface as an impermeable boundary (this is for the confined part of the model). In the unconfined part, just a sufficiently high elevation for the top slice that avoids that the water table "touches" the top boundary.

A 2D model works similar, here set the "constraints" to unconstrained and apply a sufficiently high "Aquifer top elevation" in flow material properties for the unconfined part of the model.

That depends on the purpose of the model. If you are only interested in the fate of the refrigerant that is lost through the leakage, I would rather use a simple 4th kind BC to inject this fluid where the leakage is expected, without doing any changes to the remaining model.

You should rather use the mesh export option that is available for example in the "Halt&View Results" dialog of the postprocessor or when using the "special" tool in the flow intials.

In the red box on the lower right, hit the "Mesh" button and choose file name or file type.

Hard to say what causes this problem.
I tried to reproduce this using a 3 layer pseudo-1D-model (layer 1-2 HDPE and clay, following description above, all layers horizontally), plus a 2 m layer below (with standard FEFLOW parameters). top BC is head = 24.2 m, bottom BC = 20.2 (no-Flow BC else)
The resulting flux brings a nearly perfect match with the analytic solution (deviation below 0.001 %). Do you think my model is representative?

regards,
Alex

Dear all,
please follow this link to a step-by-step example for creating and compiling an Ifm module with Visual Studio 2008. It includes the handling of 64-bit modules.
[url=http://www.feflow.info/uploads/media/ifm_example_VS2008.pdf]
http://www.feflow.info/uploads/media/ifm_example_VS2008.pdf[/url]

Hi Gemma,

The issue you have is related to the way how the mass flux BC are defined and about the choice between the two formulations of the transport equation (divergence form, convective form).

Please have a look at the attached document, it should explain the theory behind it.

If you have problems with the lateral flow, using a finer mesh should increase the accuracy of your model (Because less water is flowing laterally through your cells, where the 1st kind BC is prescribed).

best regards,
Alex.