SF_IDENT

Identification and marking of all surface nodes of the active nodes. The nodes can be addressed with the SELECT command because of this marking.

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 with the command SF_IDENT. The following commands might be used to perform the identification of the surface nodes for 3D element types only after the finite element model is read via FEM_INPUT: 

SELECT,ETYPE,S,ETYPE,SOLID_BRICK_8
SELECT,ETYPE,A,ETYPE,SOLID_TETRA_4
SELECT,ELEM,S,ETYPE
SF_IDENT

Remarks

  • In SHAPE optimization, only marked surface nodes can be defined as being design nodes. The identification of the surface nodes can be done by setting the command OPTIONS, READ_SF_IDENT = ON already during loading of the FE model (see FEM_INPUT).