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<table><tr><td>Load ID (*FLOW)</td><td>Abaqus/CAE Load/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $QnD^{(S)}$ </td><td>Not supported</td><td> $F^{-1}L^{3}T^{-1}$ </td><td>Drainage-only seepage coefficient provided on face n.</td></tr><tr><td> $QnNU^{(S)}$ </td><td>Not supported</td><td> $F^{-1}L^{3}T^{-1}$ </td><td>Nonuniform seepage coefficient and reference sink pore pressure (units of  $FL^{-2}$ ) provided on face n with magnitude supplied via user subroutine FLOW.</td></tr><tr><td>Load ID (*DFLOW)</td><td>Abaqus/CAE Load/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $Sn^{(S)}$ </td><td>Surface pore fluid</td><td> $LT^{-1}$ </td><td>Prescribed pore fluid effective velocity (outward from the face) on face n.</td></tr><tr><td> $SnNU^{(S)}$ </td><td>Not supported</td><td> $LT^{-1}$ </td><td>Nonuniform prescribed pore fluid effective velocity (outward from the face) on face n with magnitude supplied via user subroutine DFLOW.</td></tr></table>

# 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,” Section 34.4.6.

<table><tr><td>Load ID(*IMPEDANCE)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td>In</td><td>Not supported</td><td>None</td><td>Name of the impedance property that defines the impedance on face n.</td></tr></table>

# Electric fluxes

Electric fluxes are available for piezoelectric elements. They are specified as described in “Piezoelectric analysis,” Section 6.7.2.

<table><tr><td>Load ID(*DECHARGE)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $EBF^{(S)}$ </td><td>Body charge</td><td> $CL^{-3}$ </td><td>Body flux per unit volume.</td></tr><tr><td> $ESn^{(S)}$ </td><td>Surface charge</td><td> $CL^{-2}$ </td><td>Prescribed surface charge on face n.</td></tr></table>

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# 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,” Section 6.7.3; “Fully coupled thermal-electrical-structural analysis,” Section 6.7.4; and “Eddy current analysis,” Section 6.7.5.

<table><tr><td>Load ID(*DECURRENT)</td><td>Abaqus/CAE Load/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $CBF^{(S)}$ </td><td>Body current</td><td> $CL^{-3}T^{-1}$ </td><td>Volumetric current source density.</td></tr><tr><td> $CSn^{(S)}$ </td><td>Surface current</td><td> $CL^{-2}T^{-1}$ </td><td>Current density on face n.</td></tr><tr><td> $CJ^{(S)}$ </td><td>Body current density</td><td> $CL^{-2}T^{-1}$ </td><td>Volume current density vector in an eddy current analysis.</td></tr></table>

# Distributed concentration fluxes

Distributed concentration fluxes are available for mass diffusion elements. They are specified as described in “Mass diffusion analysis,” Section 6.9.1.

<table><tr><td>Load ID (*DFLUX)</td><td>Abaqus/CAE Load/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $BF^{(S)}$ </td><td>Body concentration flux</td><td> $PT^{-1}$ </td><td>Concentration body flux per unit volume.</td></tr><tr><td> $BFNU^{(S)}$ </td><td>Body concentration flux</td><td> $PT^{-1}$ </td><td>Nonuniform concentration body flux per unit volume with magnitude supplied via user subroutine DFLUX.</td></tr><tr><td> $Sn^{(S)}$ </td><td>Surface concentration flux</td><td> $PLT^{-1}$ </td><td>Concentration surface flux per unit area into face n.</td></tr><tr><td> $SnNU^{(S)}$ </td><td>Surface concentration flux</td><td> $PLT^{-1}$ </td><td>Nonuniform concentration surface flux per unit area into face n with magnitude supplied via user subroutine DFLUX.</td></tr></table>

# 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,” Section 34.4.3.

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<table><tr><td>Load ID(*DSLOAD)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td>HP(S)</td><td>Pressure</td><td> $FL^{-2}$ </td><td>Hydrostatic pressure on the element surface, linear in global Y.</td></tr><tr><td>P</td><td>Pressure</td><td> $FL^{-2}$ </td><td>Pressure on the element surface.</td></tr><tr><td>PNU</td><td>Pressure</td><td> $FL^{-2}$ </td><td>Nonuniform pressure on the element surface with magnitude supplied via user subroutine DLOAD in Abaqus/Standard and VDLOAD in Abaqus/Explicit.</td></tr><tr><td>SP(E)</td><td>Pressure</td><td> $FL^{-4}T^{2}$ </td><td>Stagnation pressure on the element surface.</td></tr><tr><td>TRSHR</td><td>Surface traction</td><td> $FL^{-2}$ </td><td>Shear traction on the element surface.</td></tr><tr><td>TRSHRNU(S)</td><td>Surface traction</td><td> $FL^{-2}$ </td><td>Nonuniform shear traction on the element surface with magnitude and direction supplied via user subroutine UTRACLOAD.</td></tr><tr><td>TRVEC</td><td>Surface traction</td><td> $FL^{-2}$ </td><td>General traction on the element surface.</td></tr><tr><td>TRVECNU(S)</td><td>Surface traction</td><td> $FL^{-2}$ </td><td>Nonuniform general traction on the element surface with magnitude and direction supplied via user subroutine UTRACLOAD.</td></tr><tr><td>VP(E)</td><td>Pressure</td><td> $FL^{-3}T$ </td><td>Viscous pressure on the element surface. The viscous pressure is proportional to the velocity normal to the element surface and opposing the motion.</td></tr></table>

# 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,” Section 34.4.4.

<table><tr><td>Load ID(*DSFLUX)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td>S</td><td>Surface heat flux</td><td> $JL^{-2}T^{-1}$ </td><td>Heat surface flux per unit area into the element surface.</td></tr></table>

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<table><tr><td>Load ID(*DSFLUX)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td>SNU</td><td>Surface heat flux</td><td> $JL^{-2}T^{-1}$ </td><td>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.</td></tr></table>

# Film conditions

Surface-based film conditions are available for all elements with temperature degrees of freedom. They are specified as described in “Thermal loads,” Section 34.4.4.

<table><tr><td>Load ID(*SFILM)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td>F</td><td>Surface film condition</td><td> $JL^{-2}T^{-1}\theta^{-1}$ </td><td>Film coefficient and sink temperature (units of  $\theta$ ) provided on the element surface.</td></tr><tr><td> $FNU^{(S)}$ </td><td>Surface film condition</td><td> $JL^{-2}T^{-1}\theta^{-1}$ </td><td>Nonuniform film coefficient and sink temperature (units of  $\theta$ ) provided on the element surface with magnitude supplied via user subroutine  $FILM$ .</td></tr></table>

# Radiation types

Surface-based radiation conditions are available for all elements with temperature degrees of freedom. They are specified as described in “Thermal loads,” Section 34.4.4.

<table><tr><td>Load ID(*SRADIATE)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td>R</td><td>Surface radiation</td><td>Dimensionless</td><td>Emissivity and sink temperature (units of θ) provided on the element surface.</td></tr></table>

# 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,” Section 34.4.7.

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<table><tr><td>Load ID(*SFLOW)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $Q^{(S)}$ </td><td>Not supported</td><td> $F^{-1}L^{3}T^{-1}$ </td><td>Seepage coefficient and reference sink pore pressure (units of  $FL^{-2}$ ) provided on the element surface.</td></tr><tr><td> $QD^{(S)}$ </td><td>Not supported</td><td> $F^{-1}L^{3}T^{-1}$ </td><td>Drainage-only seepage coefficient provided on the element surface.</td></tr><tr><td> $QNU^{(S)}$ </td><td>Not supported</td><td> $F^{-1}L^{3}T^{-1}$ </td><td>Nonuniform seepage coefficient and reference sink pore pressure (units of  $FL^{-2}$ ) provided on the element surface with magnitude supplied via user subroutine FLOW.</td></tr><tr><td>Load ID(*DSFLOW)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $S^{(S)}$ </td><td>Surface pore fluid</td><td> $LT^{-1}$ </td><td>Prescribed pore fluid effective velocity outward from the element surface.</td></tr><tr><td> $SNU^{(S)}$ </td><td>Surface pore fluid</td><td> $LT^{-1}$ </td><td>Nonuniform prescribed pore fluid effective velocity outward from the element surface with magnitude supplied via user subroutine DFLOW.</td></tr></table>

# 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,” Section 34.4.6.

# 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,” Section 34.4.6. 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,” Section 6.7.2.

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<table><tr><td>Load ID(*DSECHARGE)</td><td>Abaqus/CAELoad/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $ES^{(S)}$ </td><td>Surface charge</td><td> $CL^{-2}$ </td><td>Prescribed surface charge on the element surface.</td></tr></table>

# 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,” Section 6.7.3; “Fully coupled thermal-electrical-structural analysis,” Section 6.7.4; and “Eddy current analysis,” Section 6.7.5.

<table><tr><td>Load ID (*DSECURRENT)</td><td>Abaqus/CAE Load/Interaction</td><td>Units</td><td>Description</td></tr><tr><td> $CS^{(S)}$ </td><td>Surface current</td><td> $CL^{-2}T^{-1}$ </td><td>Current density applied on the element surface.</td></tr><tr><td> $CK^{(S)}$ </td><td>Surface current density</td><td> $CL^{-1}T^{-1}$ </td><td>Surface current density vector in an eddy current analysis.</td></tr></table>

# 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,” Section 2.2.5) in which case output is in the local coordinate system (which rotates with the motion in large-displacement analysis). See “State storage,” Section 1.5.4 of the Abaqus Theory Guide, 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 , direct stress.

S22 , direct stress.

S33 , direct stress (not available for plane stress elements).

S12 , 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.

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# 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.

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# 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

![](images/page-138_96dffe9386f0ef6dc59847f2952b68705f0085e7196aa8601d105d904c227be6.jpg)

<details>
<summary>text_image</summary>

3
face 3
face 2
1
face 1
2
</details>

3 - node element

![](images/page-138_37a5f63308d23e323774d84664df4b478136bcefa32c972ff6a98916a3148d86.jpg)

<details>
<summary>text_image</summary>

face 3
face 4
face 2
face 1
face 4
</details>

4 - node element

![](images/page-138_0a0b68662ff2830f1a0be68965a3071e5848d91789d258f0a70f84f245399654.jpg)

![](images/page-138_e7b8504d0a960650dc0719cbdf0701430a3e59862d63407913616dbb9abb7604.jpg)

<details>
<summary>flowchart</summary>

```mermaid
graph TD
    1["1"] --> 6["6"]
    6 --> 3["3"]
    3 --> 5["5"]
    5 --> 2["2"]
    2 --> 4["4"]
    4 --> 1["1"]
    3 --> 2["2"]
    2 --> 1["1"]
    1 --> 3["3"]
    3 --> 5["5"]
    5 --> 6["6"]
```
</details>

6 - node element

![](images/page-138_3b57cf4cdedeb3973e92d0a139e101e9af1f9910aab1f9500d720bc8b853a8f0.jpg)

<details>
<summary>flowchart</summary>

```mermaid
graph TD
    1 --> 2
    1 --> 5
    1 --> 8
    2 --> 3
    2 --> 6
    3 --> 4
    3 --> 7
    4 --> 8
    5 --> 8
    6 --> 7
    7 --> 8
    8 --> 4
    7 --> 3
    6 --> 2
    5 --> 1
    4 --> 3
    3 --> 6
    2 --> 5
    1 --> 8
    3 --> 6
    4 --> 8
    5 --> 8
    6 --> 7
    7 --> 8
    8 --> 4
    7 --> 3
    6 --> 2
    5 --> 1
    4 --> 3
    3 --> 6
    2 --> 5
    1 --> 8
    3 --> 6
    5 --> 8
    7 --> 3
    8 --> 4
    6 --> 5
    5 --> 8
    4 --> 7
    3 --> 6
    2 --> 8
    1 --> 5
    3 --> 6
    5 --> 8
    7 --> 3
    8 --> 4
```
</details>

8 - node element

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

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not incremented when the elements are generated incrementally (see “Creating elements from existing elements by generating them incrementally” in “Element definition,” Section 2.2.1).

Triangular element faces 

<table><tr><td>Face 1</td><td>1 - 2 face</td></tr><tr><td>Face 2</td><td>2 - 3 face</td></tr><tr><td>Face 3</td><td>3 - 1 face</td></tr></table>

Quadrilateral element faces 

<table><tr><td>Face 1</td><td>1 - 2 face</td></tr><tr><td>Face 2</td><td>2 - 3 face</td></tr><tr><td>Face 3</td><td>3 - 4 face</td></tr><tr><td>Face 4</td><td>4 - 1 face</td></tr></table>

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![](images/page-140_1e0b335a4bd586ef25e1bbcf69d195784918a5cb60497af2f0dfcf8dad3d9ff5.jpg)

<details>
<summary>text_image</summary>

3
×1
1
2
</details>

3 - node element

![](images/page-140_b2057f865a07b11fa80f25d7b5be0e3746fc21f1779ef30e21104a2625d67ae1.jpg)

<details>
<summary>flowchart</summary>

```mermaid
graph TD
    1 -->|×1| 4
    1 -->|×1| 6
    4 -->|×2| 2
    4 -->|×3| 3
    2 -->|×3| 5
    3 -->|×3| 5
    5 -->|×2| 2
```
</details>

6 - node element

![](images/page-140_3ff946285bfd0ea18ea0d93bfdb7cbd203881a554e7caa94e15e4b29c6dd40a6.jpg)

<details>
<summary>text_image</summary>

4 ×3 4×
×1 2×
1 2
</details>

4 - node element

![](images/page-140_7767b432159ec87b3179e142bac22ee6a6c8bf7fb9f40914694b8d665b65c0d4.jpg)

<details>
<summary>text_image</summary>

4
×1
1
3
2
</details>

4-node reduced integration element

![](images/page-140_8037f3603be944c5c946692c57d4e72f07e9f6a33fc640c4dc7a80afdb713152.jpg)

<details>
<summary>text_image</summary>

4
×7 ×8 ×9
8 ×4 ×5 ×6
×1 ×2 ×3
1 5 2
3
6
2
</details>

8 - node element

![](images/page-140_79be95ca7ea5e46d13f7e6501a4aa2c35302b2ebaae7da23dc32618c5cda6cc4.jpg)

<details>
<summary>text_image</summary>

4
×3
7
4×
3
8
×1
1
5
2×
6
2
</details>

8-node reduced integration element

For heat transfer applications a different integration scheme is used for triangular elements, as described in “Triangular, tetrahedral, and wedge elements,” Section 3.2.6 of the Abaqus Theory Guide.
