Identifying Surface Nodes for Shape Optimization

The identification of surface nodes is necessary for shape optimization. During the optimization preprocessing the surface nodes are automatically identified when the design variables are defined (DV_SHAPE).

See Also
In Other Guides
DV_SHAPE
OPTIONS
SF_IDENT

The surface nodes can already be identified when reading the analysis model, such that a selection of the surface nodes is possible for the definition of groups. When using the parameter READ_SF_IDENT = ON in the OPTIONS command, all surface nodes are identified and can be used for further definitions.

In certain cases, problems can occur in the surface node recognition for the whole model. In these cases, only the elements should be selected which are meant to be assigned with the surface nodes. For example, if shells lie on the surface of solid elements, only the free boundary of the shell is identified as being a surface. In this case, the solid elements must be selected (command SELECT) and their surface nodes must be identified with the command SF_IDENT. The command SF_IDENT can only be used once.