Design variables (DV

In bead optimization shell models may be modified by moving the nodes perpendicular to the shells. Only nodes which are members of a shell element may be used as design nodes. Nodes for solid elements cannot be design nodes.

Define a Design variable in Tosca ANSA® environment

Choose DESIGN AREA in the Task manager and select Edit.
In DV_BEAD dialog, select the node group of design nodes.

Define a Design variable in Tosca Structure.gui

Choose Command > DV_BEAD in Tosca Structure.pre.
In the DV_BEAD dialog, select a node group and assign an ID_NAME for further reference to the definition.

Important:

For BEAD_CONTROLLER the nodes are only moved in the positive direction of the shells determined by the element definition in the FE analysis. For BEAD_SENSITIVITY the nodes may move in both the positive (GROW) as well as the negative (SHRINK) normal direction.
If you want to have nodal movement in negative normal direction and want to use BEAD_CONTROLLER invert the optimization displacement direction by defining a negative SCALE factor in the OPT_PARAM command. This has no effect for BEAD_SENSITIVITY.

The following figure shows the optimization displacement direction for bead optimization:

BEAD_SENSITIVITY is restricted to use only certain shell elements. Please consult the table below:

Valid element types for sensitivity based bead optimization	Abaqus element type	ANSYS® element type
Shell elements
SHELL_TRIANG_3	S3 S3R STRI3
SHELL_TRIANG_6
SHELL_QUAD_4	S4 S4R	SHELL143 SHELL181 SHELL41 SHELL43 SHELL63
SHELL_QUAD_8	S8R	SHELL93

Valid element types attached to the design nodes for sensitivity based bead optimization	MSC Nastran® element type	MSC Marc® element type	PERMAS® element type
Shell elements
SHELL_TRIANG_3	CTRIA3 CTRIAR	138	TRIA3 TRIA3K
SHELL_TRIANG_6	CTRIA6 CTRIAX6
SHELL_QUAD_4	CQUAD4 CQUADR CSHEAR	18 139 140	QUAD4
SHELL_QUAD_8	CQUAD8	30 72

Design variables (DV_BEAD)

Define a Design variable in Tosca ANSA® environment

Define a Design variable in Tosca Structure.gui