Supported Element Types

In topology optimization only the type of elements that are supported can be used in the design area. All other element types in the analysis model are regarded as dummy elements, that is, the elements are not modified during the optimization. Some further restrictions might apply regarding specific design responses. Check remarks for this.

Tosca Structure-element type

ANSYS®-element type

Design element

BEAM_2D

BEAM23

LINK1

LINK10

LINK11

LINK180

LINK8

BEAM3

only allowed as restriction element for shape optimizations

BEAM_3D

BEAM188

S (only the linear variant), Z used as restriction element for shape optimizations

BEAM_3D

BEAM24

BEAM4

only allowed as restriction element for shape optimizations

MASS_1

MATRIX27

F

PLANE_QUAD_4

PLANE182

C, S, F

PLANE42

C, S, F

PLANE_TRIANG_6

PLANE146

C, S, F

PLANE_QUAD_8

PLANE145

PLANE183

PLANE82

C, S, F

SHELL_QUAD_4

SHELL143

SHELL181*

SHELL41

SHELL43

SHELL63

C, S, F

SHELL_QUAD_8

SHELL150

SHELL93

SHELL281*

C, S, F

SOLID_TETRA_4

SOLID285

C, S, STS, F

SOLID_TETRA_10

SOLID148

SOLID187

SOLID92

C, S, STS, F

SOLID_BRICK_8

SOLID185

SOLID45

C, S, STS, F

SOLID_BRICK_20

SOLID147

SOLID186

SOLID95

C, S, F

SOLID_PYRAM_5

SOLID185

SOLID45

C

SOLID_PYRAM_13

SOLID147

SOLID186

SOLID95

C

DUMMY_ELEM_TYPE

all not supported element types

C=allowed for controller-based optimization (bead, shape, and topology)

S=allowed for sensitivity-based topology optimization

STS = allowed for sensitivity-based shape optimization using internal sensitivity calculation routines

F=allowed for the design responses that use the element-based reaction and internal forces

Z=allowed for sizing optimization

* = shell elements admitted for sizing optimization

For shape and bead optimization, only nodes belonging to elements supported by Tosca Structure can be used as design nodes, see About Design Variables (DV_SHAPE) and Design Variables (DV_BEAD) for details.

More solver-specific information about the sensitivity-based algorithm is found in Remarks for Sensitivity-Based Optimizations. For sensitivity-based bead optimization, see Special Remarks Using Sensitivity-Based Algorithm.

In ANSYS®, elements with pressure degrees of freedom are supported for acoustic analyses in the context of NVH optimization.

Remarks

Important:

  • In shape optimization, the form of the shell structure is optimized and not its thickness. This means that the shell edges are modified and that modifications on shell level are not carried out.
  • Shell elements are not admitted for stresses in topology optimization.
  • Second-order elements (like SOLID186) with suppressed midside nodes (as transition between first order and second order elements) are not supported by Tosca Structure.