3D-Layer Configuration Dialog

3D Layer Configuration is used for switching the model type from 2D to 3D and vice versa, for setting up the basic 3D structure, or for changing the model layering later on. It can also be used for creating layer pinch-outs using tetrahedral elements and for assigning elevations to the nodes.

As a general principle, none of the changes performed in the layer configuration dialog are applied to the model while the dialog is opened. Only when closing it by pressing the OK button, the changes are applied. The Elevations and 3D View tabs in the 3D Layer Configurator dialog however provide a preview of what the model will look like with the current settings.

Toolbar

Symbol	Name	Operation
	Insert slice(s) above...	Add one or several slices above the selected one.
	Insert slice(s) below...	Add one or several slices below the selected one.
	Insert slice(s) between...	Add one or several slices between the two selected ones.
	Change distance between slices...	Change the distance between the selected two slices.
	Apply elevations...	Associate a point file with elevation data with one or all slices.
	Collapse thin elements...	Merge the bottom and top faces of elements having vertical edges smaller than a defined minimum height. This e.g. enables portions of layers with extremely thin layer thickness to be removed.
	Remove	Delete the selected slice(s)
	Start / stop recording macro...	Start recording the performed actions in a macro or stop the current recording.
	Run macro...	Load and run a macro.

By using either the Insert slice (s) above or Insert slice (s) below buttons, a small dialog will be displayed. The user needs to provide the exact number of slices and their inter-distance. The reference slice is the one selected on the Slice column.

Dialog Insert slice (s) above and below.

In the case the Insert slice (s) between option is chosen, the corresponding dialog provides the possibility to introduce additional slices either equally distributed (i.e. a homogeneous subdivision of the previous layer thickness) or following a gradual increase/decrease on the inter-slice distance.

Dialog Insert slice (s) between.

The gradual increase/decrease of the layer thickness (or inter-slice distance) is controlled by a stretch factor. This factor is converted into weights for the Non-Uniform Rational B-Spline Curve (NURBS) that is used to generate the slice positions. There are basically three possible configurations:

A stretch factor < 1 is used for generating a gradation with decreasing thickness (from top slice).
A stretch factor > 1 is used for generating a gradation with increasing thickness (from top slice).
A stretch factor = 1 is used for generating an equal gradation (a uniform subdivision).

Workflow Principle

In the 3D Layer Configurator table (left side of the dialog), all slices are listed with their elevation at the position specified in the Elevations tab. The table shows the slices number, the Elevation at the point specified in the Elevations tab, and the Horizon Class currently applied.

The Elevation can be edited manually or with the help of map files. If a manual edition is desired, a double click on the elevation field (right next to the slice number) will activate the edition mode. Map files containing the elevation information can be used to assign elevation to one single slice, to a group of slices or to all available slices. For the first and simple case, the minimum requirement is that the file contains the information of the coordinates X, Y and Z. For the second and third cases, a Slice information is required into the map file. The assignment in all the cases can be executed by either a drap-and-drop operation or with the Apply elevations button.

For a quick assignment of the elevation, the map information can be applied to a target slice by a simple drag-and-drop action. A map file available in the Maps panel can be dropped onto the 3D Layer Configurator dialog. If the column headers in the file (without having intrinsically the geometrical data, e.g. ESRI Shapefiles) are named as X, Y and Z, FEFLOW will automatically assign the elevation and carry out an on-the-fly interpolation. If the column headers possess another name, FEFLOW will bring the Apply Elevation dialog, where the name of the column containing the elevation needs to be specified.

Principle of Horizon Classes

During the interpolation of a slice elevation, FEFLOW will decide whether a slice has to be moved upward or downward. Depending on the configuration of the slices and the elevation data, two or more slices can collapse, i.e., intersect each-other. The decision about the new location of the slices will depend on their so-called Horizon Classes. By default, FEFLOW provides the two horizon classes Movable and Fixed. The user can define the class type by double-clicking on the name (right column) in the data table. Alternatively, a multiple selection can be carried out and a common class can be applied by using the Class List below the data table and clicking on the Assign checkmark button.

By using the Edit horizon classes button, additional horizon classes can be added. All horizon classes have a specified order that defines their movability. When two slices intersect their horizon classes define which slice is moved and which slice isn't.

Dialog Edit Horizon Classes.

Further details about the horizon classes and their operation can be found in section Layer Pinching Workflow.

Recording the Workflow

Using the Recording macro button, the entire workflow of elevation assignment, slice insertion/deletion and horizon class definition is recorded in an external file, Layer Configurator Macro, *.lcm. By default the file is saved in the import+export folder and can be automatically recognized by pressing the Run macro button. The macro file provides fast manner to reconstruct or build a 3D model domain. Further details about the macro operation are discussed in section Using a Macro to Build the 3D Mesh.

Elevation Preview

The 3D Layer Configurator dialog provides a 2D and 3D visualization option. the 3D View tab allows the user to zoom in/out, rotate and change the vertical exaggeration of the model domain. The Elevations tab is a cross-sectional view parallel to the XY-plane, which can display an overview of the vertical layering of the model at coordinate pairs (X,Y).

Inheritance of Data From Existing to New Slices/Layers

In the Data Flow part, the data inheritance from old to new slices/layers can be controlled in case of adding or removing layers. The inheritance is defined by linking properties of old slices/layers to new ones (the ones after the change).

Reduce to 2D

If desired, a 3D model domain can be reduced to 2D by using the Reduce to 2D button.