Domain Definition Concepts

Geometry type is selected in the Geometry Information dialog Window. In this dialog window, users specify the Type of Geometry, the Domain Definition, the Length Units, and the size of the Initial Workspace (approximate size of the transport domain).

Simple Domains

The transport domain may be defined using relatively simple two-dimensional rectangular or three-dimensional hexahedral objects. In that case, the dimensions and other parameters of the transport domain are specified numerically using either the Rectangular or Hexahedral Domain Definition dialog windows. In both of these cases the transport domain is discretized into a structured finite element mesh.

General Domains

Alternatively, a more general geometry can be defined from one or more components - surfaces. Surfaces are formed by their boundary curves that can consist of any combination of polylines, arcs, circles or splines. The program also permits one to specify internal boundaries (e.g., drains, wells, impermeable objects), as well as internal curves and points. A user can define from these objects either a two-dimensional transport domain or the base plane (Base Surface) of the 3D-Layered domain which is then extruded to 3D with the help of thickness vectors. In both of these cases the transport domain is discretized into an unstructured finite element mesh.

In the 3D-Standard version, the Geometry is defined using the Base Surface, which is a 2D domain of an arbitrary shape, and a set of Thickness Vectors, that define the variable thickness of the 3D domain or thicknesses of an arbitrary number of Geo-Layers (called Sub-Layers in Version 1). Such domain is then called the 3D-Layered domain. Although such domains can not be fully general, they allow definition of a majority of realistic 3D problems.

In the 3D-Professional version, the Geometry (general three-dimensional domains) can be formed from three-dimensional objects (Solids, bodies) of general shapes. Three-dimensional objects are formed by boundary surfaces, which can be either Planar surfaces or curved surfaces (Quadrangle, Rotary, Pipe, B-Spline). In more complicated cases it is also possible to use Intersections of surfaces and solids and to create in this way openings in solids or to carry out with solids logical operations.