Home > User Guide > Model Analysis
Cellular Topology
The Cellular Topology Component (CT), allows modeling of subregions in a solid. For instance, to represent a solid made up of two different materials laminated together, one could use cells with different material properties attached to them. These cells can be either 2D sheets or 3D solids. The benefit of this is that unique information can be associated with each cell. In finite element and finite difference analysis (for example, used to analyze stress, temperature, and magnetic fields), a model is subdivided into a number of geometrically simple regions for the purpose of simplifying the calculations. Cells can be used to represent this type of subdivision, too.
CT is merely a data structure on top of the normal ACIS topology. It is very general, very flexible, and low-level. This auxiliary data structure organizes models with mixed dimensionality into the solid and sheet cells from which they are composed. A single lump can potentially contain many solid and sheet regions. CT computes, maintains, and edits a secondary representation, attached through attributes, that stores all solid and sheet cells, as well as the face "uses" that comprise them. This data may be attached to or removed from any lump at any time.
Lumps are defined as connected regions of mixed dimensionality. Shells are defined as connected face sets, for example:
- A 2D sheet is a single lump and shell.
- A solid, decomposed into many smaller solids by internal double-sided faces, all of which are interconnected, is a single lump and shell.
- A solid containing a disconnected, embedded set of faces consists of two shells. The embedded shell need not be closed.
- A body consisting of a block and a disconnected, non-embedded sheet (double-sided, both-outside) face is represented by two lumps.
Note, however, that cellular topology cannot be attached to a body containing an incomplete shell. A consequence of this is that an operation on a body which would result in an incomplete body will fail if the body has cellular topology attached. Refer to the section Automatic Recompute for details on how to control this behavior.
Topics include:
[Top]
© 1989-2007 Spatial Corp., a Dassault Systèmes company. All rights reserved.