Design Variables
Design variable entities define and store design variables for optimization problems.
Design variables do not have a display state in the modeling window.
Nastran Cards
Card  Description 

DESVAR  Defines a design variable for design optimization. Note: Design variable
definition.

DLINK  Relates one design variable to one or more other design
variables. Note: Design variable link.

OptiStruct Cards
Card  Description 

DCOMP  Defines manufacturing constraints for composite sizing
optimization. Note: Bulk Data Entry

DESVAR  Defines a design variable. Note: Bulk Data Entry

DSHAPE  Defines parameters for the generation of freeshape design
variables. Note: Bulk Data Entry

DSHUFFLE  Defines parameters for the generation of composite
shuffling design variables. Note: Bulk Data Entry

DSIZE  Defines parameters for the generation of freesize design
variables. Note: Bulk Data Entry

DTPG  Defines parameters for the generation of topography design
variables. Note: Bulk Data Entry

DTPL  Defines parameters for the generation of topology design
variables. Note: Bulk Data Entry

DVGRID  Defines the relationship between a design variable and a
grid point location. Note: Bulk Data Entry
Exported in large field format by both the optistruct and optistructlf templates. 
Radioss Cards
Card  Description 

DESVAR  Defines an optimization design variable (max. or min.). 
DSHAPE  Design variable for FreeShape optimization. 
DSIZE  Design variable for FreeSize optimization. 
DTPG  Design variable for Topography optimization. 
DTPL  Design variable for Topology optimization. 
DVPREL1  Defined linearly, relates a design variable to an analysis model property using the equation. 
DVGRID  Defines the relationship between design variable and grid point location. 