Elements

OptiStruct Keyword

Notes

CBAR

Defines a simple beam element. Represented in HyperMesh as a bar2 element type.

CBEAM

Defines a beam element. Represented in HyperMesh as a bar2 element type.

CBUSH

Defines a generalized spring element. Represented in HyperMesh as a spring element type.

CDAMP1

Defines a scalar damper element. Represented in HyperMesh as a spring element type or as a mass element type (grounded CDAMP1).

CDAMP2

Defines a scalar damper element, without reference to a property. Represented in HyperMesh as a spring element type or as a mass element type (grounded CDAMP2).

CDAMP3

Defines a scalar damper element that is connected only to scalar points. Represented in HyperMesh as a spring element type or as a mass element type (when a coordinate is constrained).

CDAMP4

Defines a scalar damper element that is connected only to scalar points and is without reference to a property. Represented in HyperMesh as a spring element type or as a mass element type (when a coordinate is constrained).

CELAS1

Defines a scalar spring element. Represented in HyperMesh as a spring element type or as a mass element type (grounded CELAS1).

CELAS2

Defines a scalar spring element, without reference to a property. Represented in HyperMesh as a spring element type or as a mass element type (grounded CELAS2).

Exported in large field format by optistructlf template.

CELAS3

Defines a scalar spring element that is connected only to scalar points. Represented in HyperMesh as a spring element type or as a mass element type (when a coordinate is constrained).

CELAS4

Defines a scalar spring element that is connected only to scalar points and is without reference to a property. Represented in HyperMesh as a spring element type or as a mass element type (when a coordinate is constrained).

CGAP

Defines a node-to-node gap or friction element. Represented in HyperMesh as a gap element type. HyperMesh automatically determines the type of gap elements (either CGAP or CGAPG) based on whether the element is node-to-node or node-to-elem.

CGAPG

Defines a node-to-elem gap or friction element. Represented in HyperMesh as a gap element type. HyperMesh automatically determines the type of gap elements (either CGAP or CGAPG) based on whether the element is node-to-node or node-to-elem.

CHEXA
(8-noded)

Defines a first order solid element, composed of 6 quadrilateral faces. Represented in HyperMesh as a hex8 element type.

CHEXA
(20-noded)

Defines a second order solid element, composed of 6 quadrilateral faces. Represented in HyperMesh as a hex20 element type.

A second order element with missing mid-side nodes can be defined in OptiStruct. Input data decks containing such elements are read by the translator as a first-order element. A message is written to the OptiStruct.msg file indicating the corresponding element ID.

CMASS1

Defines a scalar mass element. Represented in HyperMesh as a spring element type or as a mass element type (grounded CMASS1).

CMASS2

Defines a scalar mass element, without reference to a property. Represented in HyperMesh as a spring element type or as a mass element type (grounded CMASS2).

CMASS3

Defines a scalar mass element that is connected only to scalar points. Represented in HyperMesh as a spring element type or as a mass element type (when a coordinate is constrained).

CMASS4

Defines a scalar mass element that is connected only to scalar points and is without reference to a property. Represented in HyperMesh as a spring element type or as a mass element type (when a coordinate is constrained).

CONM1

Defines a 6x6 mass matrix at a grid point. Represented in HyperMesh as a mass element type.

CONM2

Defines a concentrated mass at a grid point. Represented in HyperMesh as a mass element type.

Exported in large field format by optistructlf template.

CONROD

Defines a rod element without reference to a property. Represented in HyperMesh as a rod element type.

CPENTA
(6-noded)

Defines a first order solid element, composed of 3 quadrilateral and 2 triangular faces. Represented in HyperMesh as a penta6 element type.

CPENTA
(15-noded)

Defines a second order solid element, composed of 3 quadrilateral and 2 triangular faces. Represented in HyperMesh as a penta15 element type.

A second order element with missing mid-side nodes can be defined in OptiStruct. Input data decks containing such elements are read by the translator as a first-order element. A message is written to the OptiStruct.msg file indicating the corresponding element ID.

CPYRA
(5-noded)

Defines a first order solid element, composed of 1 quadrilateral and 4 triangular faces. Represented in HyperMesh as a pyramid5 element type.

CPYRA
(13-noded)

Defines a second order solid element, composed of 1 quadrilateral and 4 triangular faces. Represented in HyperMesh as a pyramid13 element type.

A second order element with missing mid-side nodes can be defined in OptiStruct. Input data decks containing such elements are read by the translator as a first-order element. A message is written to the OptiStruct.msg file indicating the corresponding element ID.

CQUAD4

Defines a first order quadrilateral element. Represented in HyperMesh as a quad4 element type.

CQUAD8

Defines a second order quadrilateral element. Represented in HyperMesh as a quad8 element type.

CROD

Defines a tension-compression element. Represented in HyperMesh as a rod element type.

CSHEAR

Defines a shear panel element. Represented in HyperMesh as a quad4 element type.

CTETRA
(4-noded)

Defines a first order solid element, composed of 4 triangular faces. Represented in HyperMesh as a tetra4 element type.

CTETRA
(10-noded)

Defines a second order solid element, composed of 4 triangular faces. Represented in HyperMesh as a tetra10 element type.

A second order element with missing mid-side nodes can be defined in OptiStruct. Input data decks containing such elements are read by the translator as a first-order element. A message is written to the OptiStruct.msg file indicating the corresponding element ID.

CTRIA3

Defines a first order triangular element. Represented in HyperMesh as a tria3 element type.

CTRIA6

Defines a second order triangular element. Represented in HyperMesh as a tria6 element type.

CVISC

Defines a viscous damper element. Represented in HyperMesh as a spring element type.

CWELD

Defines a weld or fastener connecting two surface patches or points. Represented in HyperMesh as a rod element type.

PLOTEL

Defines a 1-dimensional dummy element, for use in plotting. Represented in HyperMesh as a plot element type.

RBAR

Defines a rigid bar with 6 degrees of freedom at each end. Represented in HyperMesh as a weld element type.

RBE2

Defines a rigid body whose independent degrees of freedom are specified at a single grid point and whose dependent degrees of freedom are specified at an arbitrary number of grid points. An RBE2 element with one dependent node is represented in HyperMesh as a rigid element type, while an element with multiple dependent nodes is represented in HyperMesh as a rigid link element type.

RBE3

Defines the motion at a "reference" grid point as the weighted average of the motions at a set of other grid points. Represented in HyperMesh as an rbe3 element type.

RROD

Defines a pin-ended rod that is rigid in extension. Represented in HyperMesh as a rod element type.

HMSPRING

Defines a HyperMesh Spring element, which is converted to OptiStruct entities on export, in a manner similar to that explained in Using HM_ELAS.

OptiStruct Keyword

Notes

CMBEAM

Defines a beam element for multi-body dynamics solution sequence without reference to a property. Represented in HyperMesh as a bar2 element type.

CMSPDP

Defines a spring damper element for multi-body dynamics solution sequence without reference to a property. Represented in HyperMesh as a spring element type.

JOINT

Defines a joint for multi-body dynamics solution sequence. Represented in HyperMesh as a joint element type.