Two-dimensional solid element library

Element types

Plane strain elements

CPE3: 3-node linear
CPE3H^(S): 3-node linear, hybrid with constant pressure
CPE4^(S): 4-node bilinear
CPE4H^(S): 4-node bilinear, hybrid with constant pressure
CPE4I^(S): 4-node bilinear, incompatible modes
CPE4IH^(S): 4-node bilinear, incompatible modes, hybrid with linear pressure
CPE4R: 4-node bilinear, reduced integration with hourglass control
CPE4RH^(S): 4-node bilinear, reduced integration with hourglass control, hybrid with constant pressure
CPE6^(S): 6-node quadratic
CPE6H^(S): 6-node quadratic, hybrid with linear pressure
CPE6M: 6-node modified, with hourglass control
CPE6MH^(S): 6-node modified, with hourglass control, hybrid with linear pressure
CPE8^(S): 8-node biquadratic
CPE8H^(S): 8-node biquadratic, hybrid with linear pressure
CPE8R^(S): 8-node biquadratic, reduced integration
CPE8RH^(S): 8-node biquadratic, reduced integration, hybrid with linear pressure

Active degrees of freedom

1, 2

Additional solution variables

The constant pressure hybrid elements have one additional variable relating to pressure, and the linear pressure hybrid elements have three additional variables relating to pressure.

Element types CPE4I and CPE4IH have five additional variables relating to the incompatible modes.

Element types CPE6M and CPE6MH have two additional displacement variables.

Plane stress elements

CPS3: 3-node linear
CPS4^(S): 4-node bilinear
CPS4I^(S): 4-node bilinear, incompatible modes
CPS4R: 4-node bilinear, reduced integration with hourglass control
CPS6^(S): 6-node quadratic
CPS6M: 6-node modified, with hourglass control
CPS8^(S): 8-node biquadratic
CPS8R^(S): 8-node biquadratic, reduced integration

Active degrees of freedom

1, 2

Additional solution variables

Element type CPS4I has four additional variables relating to the incompatible modes.

Element type CPS6M has two additional displacement variables.

Generalized plane strain elements

CPEG3^(S): 3-node linear triangle
CPEG3H^(S): 3-node linear triangle, hybrid with constant pressure
CPEG4^(S): 4-node bilinear quadrilateral
CPEG4H^(S): 4-node bilinear quadrilateral, hybrid with constant pressure
CPEG4I^(S): 4-node bilinear quadrilateral, incompatible modes
CPEG4IH^(S): 4-node bilinear quadrilateral, incompatible modes, hybrid with linear pressure
CPEG4R^(S): 4-node bilinear quadrilateral, reduced integration with hourglass control
CPEG4RH^(S): 4-node bilinear quadrilateral, reduced integration with hourglass control, hybrid with constant pressure
CPEG6^(S): 6-node quadratic triangle
CPEG6H^(S): 6-node quadratic triangle, hybrid with linear pressure
CPEG6M^(S): 6-node modified, with hourglass control
CPEG6MH^(S): 6-node modified, with hourglass control, hybrid with linear pressure
CPEG8^(S): 8-node biquadratic quadrilateral
CPEG8H^(S): 8-node biquadratic quadrilateral, hybrid with linear pressure
CPEG8R^(S): 8-node biquadratic quadrilateral, reduced integration
CPEG8RH^(S): 8-node biquadratic quadrilateral, reduced integration, hybrid with linear pressure

Active degrees of freedom

1, 2 at all but the reference node

3, 4, 5 at the reference node

Additional solution variables

The constant pressure hybrid elements have one additional variable relating to pressure, and the linear pressure hybrid elements have three additional variables relating to pressure.

Element types CPEG4I and CPEG4IH have five additional variables relating to the incompatible modes.

Element types CPEG6M and CPEG6MH have two additional displacement variables.

Coupled temperature-displacement plane strain elements

CPE3T: 3-node linear displacement and temperature
CPE4T^(S): 4-node bilinear displacement and temperature
CPE4HT^(S): 4-node bilinear displacement and temperature, hybrid with constant pressure
CPE4RT: 4-node bilinear displacement and temperature, reduced integration with hourglass control
CPE4RHT^(S): 4-node bilinear displacement and temperature, reduced integration with hourglass control, hybrid with constant pressure
CPE6MT: 6-node modified displacement and temperature, with hourglass control
CPE6MHT^(S): 6-node modified displacement and temperature, with hourglass control, hybrid with constant pressure
CPE8T^(S): 8-node biquadratic displacement, bilinear temperature
CPE8HT^(S): 8-node biquadratic displacement, bilinear temperature, hybrid with linear pressure
CPE8RT^(S): 8-node biquadratic displacement, bilinear temperature, reduced integration
CPE8RHT^(S): 8-node biquadratic displacement, bilinear temperature, reduced integration, hybrid with linear pressure

Active degrees of freedom

1, 2, 11 at corner nodes

1, 2 at midside nodes of second-order elements in Abaqus/Standard

1, 2, 11 at midside nodes of modified displacement and temperature elements in Abaqus/Standard

Additional solution variables

The constant pressure hybrid elements have one additional variable relating to pressure, and the linear pressure hybrid elements have three additional variables relating to pressure.

Element types CPE6MT and CPE6MHT have two additional displacement variables and one additional temperature variable.

Coupled temperature-displacement plane stress elements

CPS3T: 3-node linear displacement and temperature
CPS4T^(S): 4-node bilinear displacement and temperature
CPS4RT: 4-node bilinear displacement and temperature, reduced integration with hourglass control
CPS6MT: 6-node modified displacement and temperature, with hourglass control
CPS8T^(S): 8-node biquadratic displacement, bilinear temperature
CPS8RT^(S): 8-node biquadratic displacement, bilinear temperature, reduced integration

Active degrees of freedom

1, 2, 11 at corner nodes

1, 2 at midside nodes of second-order elements in Abaqus/Standard

1, 2, 11 at midside nodes of modified displacement and temperature elements in Abaqus/Standard

Additional solution variables

Element type CPS6MT has two additional displacement variables and one additional temperature variable.

Coupled temperature-displacement generalized plane strain elements

CPEG3T^(S): 3-node linear displacement and temperature
CPEG3HT^(S): 3-node linear displacement and temperature, hybrid with constant pressure
CPEG4T^(S): 4-node bilinear displacement and temperature
CPEG4HT^(S): 4-node bilinear displacement and temperature, hybrid with constant pressure
CPEG4RT^(S): 4-node bilinear displacement and temperature, reduced integration with hourglass control
CPEG4RHT^(S): 4-node bilinear displacement and temperature, reduced integration with hourglass control, hybrid with constant pressure
CPEG6MT^(S): 6-node modified displacement and temperature, with hourglass control
CPEG6MHT^(S): 6-node modified displacement and temperature, with hourglass control, hybrid with constant pressure
CPEG8T^(S): 8-node biquadratic displacement, bilinear temperature
CPEG8HT^(S): 8-node biquadratic displacement, bilinear temperature, hybrid with linear pressure
CPEG8RHT^(S): 8-node biquadratic displacement, bilinear temperature, reduced integration, hybrid with linear pressure

Active degrees of freedom

1, 2, 11 at corner nodes

1, 2 at midside nodes of second-order elements

1, 2, 11 at midside nodes of modified displacement and temperature elements

3, 4, 5 at the reference node

Additional solution variables

The constant pressure hybrid elements have one additional variable relating to pressure, and the linear pressure hybrid elements have three additional variables relating to pressure.

Element types CPEG6MT and CPEG6MHT have two additional displacement variables and one additional temperature variable.

Diffusive heat transfer or mass diffusion elements

DC2D3^(S): 3-node linear
DC2D4^(S): 4-node linear
DC2D6^(S): 6-node quadratic
DC2D8^(S): 8-node biquadratic

Active degrees of freedom

Additional solution variables

None.

Forced convection/diffusion elements

DCC2D4^(S): 4-node
DCC2D4D^(S): 4-node with dispersion control

Active degrees of freedom

Additional solution variables

None.

Coupled thermal-electrical elements

DC2D3E^(S): 3-node linear
DC2D4E^(S): 4-node linear
DC2D6E^(S): 6-node quadratic
DC2D8E^(S): 8-node biquadratic

Active degrees of freedom

9, 11

Additional solution variables

None.

Pore pressure plane strain elements

CPE4P^(S): 4-node bilinear displacement and pore pressure
CPE4PH^(S): 4-node bilinear displacement and pore pressure, hybrid with constant pressure stress
CPE4RP^(S): 4-node bilinear displacement and pore pressure, reduced integration with hourglass control
CPE4RPH^(S): 4-node bilinear displacement and pore pressure, reduced integration with hourglass control, hybrid with constant pressure
CPE6MP^(S): 6-node modified displacement and pore pressure, with hourglass control
CPE6MPH^(S): 6-node modified displacement and pore pressure, with hourglass control, hybrid with linear pressure
CPE8P^(S): 8-node biquadratic displacement, bilinear pore pressure
CPE8PH^(S): 8-node biquadratic displacement, bilinear pore pressure, hybrid with linear pressure stress
CPE8RP^(S): 8-node biquadratic displacement, bilinear pore pressure, reduced integration
CPE8RPH^(S): 8-node biquadratic displacement, bilinear pore pressure, reduced integration, hybrid with linear pressure stress

Active degrees of freedom

1, 2, 8 at corner nodes

1, 2 at midside nodes for all elements except CPE6MP and CPE6MPH, which also have degree of freedom 8 active at midside nodes

Additional solution variables

The constant pressure hybrid elements have one additional variable relating to the effective pressure stress, and the linear pressure hybrid elements have three additional variables relating to the effective pressure stress to permit fully incompressible material modeling.

Element types CPE6MP and CPE6MPH have two additional displacement variables and one additional pore pressure variable.

Coupled temperature–pore pressure plane strain elements

CPE4PT^(S): 4-node bilinear displacement, pore pressure, and temperature
CPE4PHT^(S): 4-node bilinear displacement, pore pressure, and temperature; hybrid with constant pressure stress
CPE4RPT^(S): 4-node bilinear displacement, pore pressure, and temperature; reduced integration
CPE4RPHT^(S): 4-node bilinear displacement, pore pressure, and temperature; reduced integration, hybrid with constant pressure stress

Active degrees of freedom

1, 2, 8, 11 at corner nodes

Additional solution variables

The constant pressure stress hybrid elements have one additional variable relating to the effective pressure stress to permit fully incompressible material modeling.

Acoustic elements

AC2D3: 3-node linear
AC2D4^(S): 4-node bilinear
AC2D4R^(E): 4-node bilinear, reduced integration with hourglass control
AC2D6^(S): 6-node quadratic
AC2D8^(S): 8-node biquadratic

Active degrees of freedom

Additional solution variables

None.

Piezoelectric plane strain elements

CPE3E^(S): 3-node linear
CPE4E^(S): 4-node bilinear
CPE6E^(S): 6-node quadratic
CPE8E^(S): 8-node biquadratic
CPE8RE^(S): 8-node biquadratic, reduced integration

Active degrees of freedom

1, 2, 9

Additional solution variables

None.

Piezoelectric plane stress elements

CPS3E^(S): 3-node linear
CPS4E^(S): 4-node bilinear
CPS6E^(S): 6-node quadratic
CPS8E^(S): 8-node biquadratic
CPS8RE^(S): 8-node biquadratic, reduced integration

Active degrees of freedom

1, 2, 9

Additional solution variables

None.

Electromagnetic elements

EMC2D3^(S): 3-node zero-order
EMC2D4^(S): 4-node zero-order

Active degrees of freedom

Magnetic vector potential (for more information, see Boundary conditions and Boundary conditions).

Additional solution variables

None.

Nodal coordinates required

X, Y

Element property definition

For all elements except generalized plane strain elements, you must provide the element thickness; by default, unit thickness is assumed.

For generalized plane strain elements, you must provide three values: the initial length of the axial material fiber through the reference node, the initial value of $Δ ϕ_{x}$ (in radians), and the initial value of $Δ ϕ_{y}$ (in radians). If you do not provide these values, Abaqus assumes the default values of one unit as the initial length and zero for $Δ ϕ_{x}$ and $Δ ϕ_{y}$ . In addition, you must define the reference point for generalized plane strain elements.

Input File Usage

Use the following option to define the element properties for all elements except generalized plane strain elements:

SOLID SECTION

Use the following option to define the element properties for generalized plane strain elements:

SOLID SECTION, REF NODE=node number or node set name

Abaqus/CAE Usage

Property module: Create Section: select Solid as the section Category and Homogeneous, Generalized plane strain, or Electromagnetic, Solid as the section Type

Generalized plane strain sections must be assigned to regions of parts that have a reference point associated with them. To define the reference point:

Part module: ToolsReference Point: select reference point

Element-based loading

Distributed loads

Distributed loads are available for all elements with displacement degrees of freedom. They are specified as described in Distributed loads.

*dload

Load ID (*DLOAD): BX
Body force
FL⁻³
Body force in global X-direction.

Load ID (*DLOAD): BY
Body force
FL⁻³
Body force in global Y-direction.

Load ID (*DLOAD): BXNU
Body force
FL⁻³
Nonuniform body force in global X-direction with magnitude supplied via user subroutine DLOAD in Abaqus/Standard and VDLOAD in Abaqus/Explicit.

Load ID (*DLOAD): BYNU
Body force
FL⁻³
Nonuniform body force in global Y-direction with magnitude supplied via user subroutine DLOAD in Abaqus/Standard and VDLOAD in Abaqus/Explicit.

Load ID (*DLOAD): CENT^(S)
Not supported
FL⁻⁴(ML⁻³T⁻²)
Centrifugal load (magnitude is input as $ρ ω^{2}$ , where $ρ$ is the mass density per unit volume, $ω$ is the angular velocity). Not available for pore pressure elements.

Load ID (*DLOAD): CENTRIF^(S)
Rotational body force
T⁻²
Centrifugal load (magnitude is input as $ω^{2}$ , where $ω$ is the angular velocity).

Load ID (*DLOAD): CORIO^(S)
Coriolis force
FL⁻⁴T (ML⁻³T⁻¹)
Coriolis force (magnitude is input as $ρ ω$ , where $ρ$ is the mass density per unit volume, $ω$ is the angular velocity). Not available for pore pressure elements.

Load ID (*DLOAD): GRAV
Gravity
LT⁻²
Gravity loading in a specified direction (magnitude is input as acceleration).

Load ID (*DLOAD): HPn^(S)
Not supported
FL⁻²
Hydrostatic pressure on face n, linear in global Y.

Load ID (*DLOAD): Pn
Pressure
FL⁻²
Pressure on face n.

Load ID (*DLOAD): PnNU
Not supported
FL⁻²
Nonuniform pressure on face n with magnitude supplied via user subroutine DLOAD in Abaqus/Standard and VDLOAD in Abaqus/Explicit.

Load ID (*DLOAD): ROTA^(S)
Rotational body force
T⁻²
Rotary acceleration load (magnitude is input as $α$ , where $α$ is the rotary acceleration).

Load ID (*DLOAD): SBF^(E)
Not supported
FL⁻⁵T²
Stagnation body force in global X- and Y-directions.

Load ID (*DLOAD): SPn^(E)
Not supported
FL⁻⁴T²
Stagnation pressure on face n.

Load ID (*DLOAD): TRSHRn
Surface traction
FL⁻²
Shear traction on face n.

Load ID (*DLOAD): TRSHRnNU^(S)
Not supported
FL⁻²
Nonuniform shear traction on face n with magnitude and direction supplied via user subroutine UTRACLOAD.

Load ID (*DLOAD): TRVECn
Surface traction
FL⁻²
General traction on face n.

Load ID (*DLOAD): TRVECnNU^(S)
Not supported
FL⁻²
Nonuniform general traction on face n with magnitude and direction supplied via user subroutine UTRACLOAD.

Load ID (*DLOAD): VBF^(E)
Not supported
FL⁻⁴T
Viscous body force in global X- and Y-directions.

Load ID (*DLOAD): VPn^(E)
Not supported
FL⁻³T
Viscous pressure on face n, applying a pressure proportional to the velocity normal to the face and opposing the motion.

Foundations

Foundations are available for Abaqus/Standard elements with displacement degrees of freedom. They are specified as described in Element foundations.

*foundation

Load ID (*FOUNDATION): Fn^(S)
Elastic foundation
FL⁻³
Elastic foundation on face n.

Distributed heat fluxes

Distributed heat fluxes are available for all elements with temperature degrees of freedom. They are specified as described in Thermal loads.

*dflux

Load ID (*DFLUX): BF
Body heat flux
JL⁻³T⁻¹
Heat body flux per unit volume.

Load ID (*DFLUX): BFNU
Body heat flux
JL⁻³T⁻¹
Nonuniform heat body flux per unit volume with magnitude supplied via user subroutine DFLUX in Abaqus/Standard and VDFLUX in Abaqus/Explicit.

Load ID (*DFLUX): Sn
Surface heat flux
JL⁻²T⁻¹
Heat surface flux per unit area into face n.

Load ID (*DFLUX): SnNU
Not supported
JL⁻²T⁻¹
Nonuniform heat surface flux per unit area into face n with magnitude supplied via user subroutine DFLUX in Abaqus/Standard and VDFLUX in Abaqus/Explicit.

Film conditions

Film conditions are available for all elements with temperature degrees of freedom. They are specified as described in Thermal loads.

*film

Load ID (*FILM): Fn
Surface film condition
JL⁻²T⁻¹ $θ$ ⁻¹
Film coefficient and sink temperature (units of $θ$ ) provided on face n.

Load ID (*FILM): FnNU^(S)
Not supported
JL⁻²T⁻¹ $θ$ ⁻¹
Nonuniform film coefficient and sink temperature (units of $θ$ ) provided on face n with magnitude supplied via user subroutine FILM.

Radiation types

Radiation conditions are available for all elements with temperature degrees of freedom. They are specified as described in Thermal loads.

*radiate

Load ID (*RADIATE): Rn
Surface radiation
Dimensionless
Emissivity and sink temperature (units of $θ$ ) provided on face n.

Distributed flows

Distributed flows are available for all elements with pore pressure degrees of freedom. They are specified as described in Pore fluid flow.

*flow

Load ID (*FLOW): Qn^(S)
Not supported
F⁻¹L³T⁻¹
Seepage coefficient and reference sink pore pressure (units of FL⁻²) provided on face n.

Load ID (*FLOW): QnD^(S)
Not supported
F⁻¹L³T⁻¹
Drainage-only seepage coefficient provided on face n.

Load ID (*FLOW): QnNU^(S)
Not supported
F⁻¹L³T⁻¹
Nonuniform seepage coefficient and reference sink pore pressure (units of FL⁻²) provided on face n with magnitude supplied via user subroutine FLOW.

*dflow

Load ID (*DFLOW): Sn^(S)
Surface pore fluid
LT⁻¹
Prescribed pore fluid effective velocity (outward from the face) on face n.

Load ID (*DFLOW): SnNU^(S)
Not supported
LT⁻¹
Nonuniform prescribed pore fluid effective velocity (outward from the face) on face n with magnitude supplied via user subroutine DFLOW.

Distributed impedances

Distributed impedances are available for all elements with acoustic pressure degrees of freedom. They are specified as described in Acoustic and shock loads.

*impedance

Load ID (*IMPEDANCE): In
Not supported
None
Name of the impedance property that defines the impedance on face n.

Electric fluxes

Electric fluxes are available for piezoelectric elements. They are specified as described in Piezoelectric analysis.

*decharge

Load ID (*DECHARGE): EBF^(S)
Body charge
CL⁻³
Body flux per unit volume.

Load ID (*DECHARGE): ESn^(S)
Surface charge
CL⁻²
Prescribed surface charge on face n.

Distributed electric current densities

Distributed electric current densities are available for coupled thermal-electrical elements, coupled thermal-electrical-structural elements, and electromagnetic elements. They are specified as described in Coupled thermal-electrical analysis, Fully coupled thermal-electrical-structural analysis, and Eddy current analysis.

*decurrent

Load ID (*DECURRENT): CBF^(S)
Body current
CL⁻³T⁻¹
Volumetric current source density.

Load ID (*DECURRENT): CSn^(S)
Surface current
CL⁻²T⁻¹
Current density on face n.

Load ID (*DECURRENT): CJ^(S)
Body current density
CL⁻²T⁻¹
Volume current density vector in an eddy current analysis.

Distributed concentration fluxes

Distributed concentration fluxes are available for mass diffusion elements. They are specified as described in Mass diffusion analysis.

*dflux

Load ID (*DFLUX): BF^(S)
Body concentration flux
PT⁻¹
Concentration body flux per unit volume.

Load ID (*DFLUX): BFNU^(S)
Body concentration flux
PT⁻¹
Nonuniform concentration body flux per unit volume with magnitude supplied via user subroutine DFLUX.

Load ID (*DFLUX): Sn^(S)
Surface concentration flux
PLT⁻¹
Concentration surface flux per unit area into face n.

Load ID (*DFLUX): SnNU^(S)
Surface concentration flux
PLT⁻¹
Nonuniform concentration surface flux per unit area into face n with magnitude supplied via user subroutine DFLUX.

Surface-based loading

Distributed loads

Surface-based distributed loads are available for all elements with displacement degrees of freedom. They are specified as described in Distributed loads.

*dsload

Load ID (*DSLOAD): HP^(S)
Pressure
FL⁻²
Hydrostatic pressure on the element surface, linear in global Y.

Load ID (*DSLOAD): P
Pressure
FL⁻²
Pressure on the element surface.

Load ID (*DSLOAD): PNU
Pressure
FL⁻²
Nonuniform pressure on the element surface with magnitude supplied via user subroutine DLOAD in Abaqus/Standard and VDLOAD in Abaqus/Explicit.

Load ID (*DSLOAD): SP^(E)
Pressure
FL⁻⁴T²
Stagnation pressure on the element surface.

Load ID (*DSLOAD): TRSHR
Surface traction
FL⁻²
Shear traction on the element surface.

Load ID (*DSLOAD): TRSHRNU^(S)
Surface traction
FL⁻²
Nonuniform shear traction on the element surface with magnitude and direction supplied via user subroutine UTRACLOAD.

Load ID (*DSLOAD): TRVEC
Surface traction
FL⁻²
General traction on the element surface.

Load ID (*DSLOAD): TRVECNU^(S)
Surface traction
FL⁻²
Nonuniform general traction on the element surface with magnitude and direction supplied via user subroutine UTRACLOAD.

Load ID (*DSLOAD): VP^(E)
Pressure
FL⁻³T
Viscous pressure on the element surface. The viscous pressure is proportional to the velocity normal to the element surface and opposing the motion.

Distributed heat fluxes

Surface-based heat fluxes are available for all elements with temperature degrees of freedom. They are specified as described in Thermal loads.

*dsflux

Load ID (*DSFLUX): S
Surface heat flux
JL⁻²T⁻¹
Heat surface flux per unit area into the element surface.

Load ID (*DSFLUX): SNU
Surface heat flux
JL⁻²T⁻¹
Nonuniform heat surface flux per unit area applied on the element surface with magnitude supplied via user subroutine DFLUX in Abaqus/Standard and VDFLUX in Abaqus/Explicit.

Film conditions

Surface-based film conditions are available for all elements with temperature degrees of freedom. They are specified as described in Thermal loads.

*sfilm

Load ID (*SFILM): F
Surface film condition
JL⁻²T⁻¹ $θ$ ⁻¹
Film coefficient and sink temperature (units of $θ$ ) provided on the element surface.

Load ID (*SFILM): FNU^(S)
Surface film condition
JL⁻²T⁻¹ $θ$ ⁻¹
Nonuniform film coefficient and sink temperature (units of $θ$ ) provided on the element surface with magnitude supplied via user subroutine FILM.

Radiation types

Surface-based radiation conditions are available for all elements with temperature degrees of freedom. They are specified as described in Thermal loads.

*sradiate

Load ID (*SRADIATE): R
Surface radiation
Dimensionless
Emissivity and sink temperature (units of $θ$ ) provided on the element surface.

Distributed flows

Surface-based flows are available for all elements with pore pressure degrees of freedom. They are specified as described in Pore fluid flow.

*sflow

Load ID (*SFLOW): Q^(S)
Not supported
F⁻¹L³T⁻¹
Seepage coefficient and reference sink pore pressure (units of FL⁻²) provided on the element surface.

Load ID (*SFLOW): QD^(S)
Not supported
F⁻¹L³T⁻¹
Drainage-only seepage coefficient provided on the element surface.

Load ID (*SFLOW): QNU^(S)
Not supported
F⁻¹L³T⁻¹
Nonuniform seepage coefficient and reference sink pore pressure (units of FL⁻²) provided on the element surface with magnitude supplied via user subroutine FLOW.

*dsflow

Load ID (*DSFLOW): S^(S)
Surface pore fluid
LT⁻¹
Prescribed pore fluid effective velocity outward from the element surface.

Load ID (*DSFLOW): SNU^(S)
Surface pore fluid
LT⁻¹
Nonuniform prescribed pore fluid effective velocity outward from the element surface with magnitude supplied via user subroutine DFLOW.

Distributed impedances

Surface-based impedances are available for all elements with acoustic pressure degrees of freedom. They are specified as described in Acoustic and shock loads.

Incident wave loading

Surface-based incident wave loads are available for all elements with displacement degrees of freedom or acoustic pressure degrees of freedom. They are specified as described in Acoustic and shock loads. If the incident wave field includes a reflection off a plane outside the boundaries of the mesh, this effect can be included.

Electric fluxes

Surface-based electric fluxes are available for piezoelectric elements. They are specified as described in Piezoelectric analysis.

*dsecharge

Load ID (*DSECHARGE): ES^(S)
Surface charge
CL⁻²
Prescribed surface charge on the element surface.

Distributed electric current densities

Surface-based electric current densities are available for coupled thermal-electrical elements, coupled thermal-electrical-structural elements, and electromagnetic elements. They are specified as described in Coupled thermal-electrical analysis, Fully coupled thermal-electrical-structural analysis, and Eddy current analysis.

*dsecurrent

Load ID (*DSECURRENT): CS^(S)
Surface current
CL⁻²T⁻¹
Current density applied on the element surface.

Load ID (*DSECURRENT): CK^(S)
Surface current density
CL⁻¹T⁻¹
Surface current density vector in an eddy current analysis.

Element output

For most elements output is in global directions unless a local coordinate system is assigned to the element through the section definition (Orientations) in which case output is in the local coordinate system (which rotates with the motion in large-displacement analysis). See State storage for details.

Stress, strain, and other tensor components

Stress and other tensors (including strain tensors) are available for elements with displacement degrees of freedom. All tensors have the same components. For example, the stress components are as follows:

S11: $X X$ , direct stress.
S22: $Y Y$ , direct stress.
S33: $Z Z$ , direct stress (not available for plane stress elements).
S12: $X Y$ , shear stress.

Heat flux components

Available for elements with temperature degrees of freedom.

HFL1: Heat flux in the X-direction.
HFL2: Heat flux in the Y-direction.

Pore fluid velocity components

Available for elements with pore pressure degrees of freedom.

FLVEL1: Pore fluid effective velocity in the X-direction.
FLVEL2: Pore fluid effective velocity in the Y-direction.

Mass concentration flux components

Available for elements with normalized concentration degrees of freedom.

MFL1: Concentration flux in the X-direction.
MFL2: Concentration flux in the Y-direction.

Electrical potential gradient

Available for elements with electrical potential degrees of freedom.

EPG1: Electrical potential gradient in the X-direction.
EPG2: Electrical potential gradient in the Y-direction.

Electrical flux components

Available for piezoelectric elements.

EFLX1: Electrical flux in the X-direction.
EFLX2: Electrical flux in the Y-direction.

Electrical current density components

Available for coupled thermal-electrical elements.

ECD1: Electrical current density in the X-direction.
ECD2: Electrical current density in the Y-direction.

Electrical field components

Available for electromagnetic elements in an eddy current analysis.

EME1: Electric field in the X-direction.
EME2: Electric field in the Y-direction.

Magnetic flux density components

Available for electromagnetic elements.

EMB3: Magnetic flux density in the Z-direction.

Magnetic field components

Available for electromagnetic elements.

EMH3: Magnetic field in the Z-direction.

Eddy current density components in an eddy current analysis

Available for electromagnetic elements in an eddy current analysis.

EMCD1: Eddy current density in the X-direction.
EMCD2: Eddy current density in the Y-direction.

Applied volume current density components in an eddy current or magnetostatic analysis

Available for electromagnetic elements in an eddy current or magnetostatic analysis.

EMCDA1: Applied volume current density in the X-direction.
EMCDA2: Applied volume current density in the Y-direction.

Node ordering and face numbering on elements

For generalized plane strain elements, the reference node associated with each element (where the generalized plane strain degrees of freedom are stored) is not shown. The reference node should be the same for all elements in any given connected region so that the bounding planes are the same for that region. Different regions may have different reference nodes. The number of the reference node is not incremented when the elements are generated incrementally (see Creating elements from existing elements by generating them incrementally).

Table 1. Triangular element faces
Face 1	1 – 2 face
Face 2	2 – 3 face
Face 3	3 – 1 face

Table 2. Quadrilateral element faces
Face 1	1 – 2 face
Face 2	2 – 3 face
Face 3	3 – 4 face
Face 4	4 – 1 face

Numbering of integration points for output

For heat transfer applications a different integration scheme is used for triangular elements, as described in Triangular, tetrahedral, and wedge elements.