Identification: 3DRA [-] (only in 3D model file, *.3d)

The definition of a closed boundary (i.e. where the first node is equal to the last one) enlarges the part of the actual model inside this boundary into the 3rd dimension. This can be the whole 2D horizontal model or one or several parts of it. This is done via the menu Mesh 3D 3D-boundary generate/add. The numbers of the boundary nodes are stored automatically in their order and anticlockwise separately for each boundary.

To calculate multiple separate 3D areas without surrounding 2D horizontal model, these areas must have the same number of ZKOR layers, may not have any geometric overlapping and must be connected to at least one node by the attribute GLEI.

For the case of one or more partial 3D models, the boundary conditions for the 3DRA nodes can be influenced by plus and minus signs at the node numbers (see Creating 2D/3D models):

 

Positive node numbers (plus sign) mean that for the corresponding generated 3D nodes an unknown equal potential head is assumed (= only horizontal flow).

Negative node numbers (minus sign) mean that for the corresponding generated 3D nodes this boundary condition is not assumed.

The assumption of unknown equal potential heads over the whole depth as mentioned above is only possible for a partial 3D model. For a complete 3D model, the boundary conditions (potential head, reaction rates) have to be specified explicitly. Here the potential heads are not set equal over the depth.