ABAQUS Keywords Reference Manual  

*EXPANSION
Specify thermal expansion.

This option is used to define thermal expansion for a material or for the behavior of a gasket.

Products: ABAQUS/Standard  ABAQUS/Explicit  

Type: Model data

Level: Model  

References:

Optional parameters:

DEPENDENCIES

Set this parameter equal to the number of field variables, in addition to temperature, on which the coefficients depend. If this parameter is omitted, it is assumed that the thermal expansion is constant or depends only on temperature.

This parameter is not relevant if the USER parameter is included.

PORE FLUID

This parameter applies only to ABAQUS/Standard analyses.

Include this parameter if the thermal expansion of the pore fluid in a porous medium is being defined. The thermal expansion of a fluid must be isotropic, so TYPE=ORTHO and TYPE=ANISO cannot be used if this parameter is included.

TYPE

Set TYPE=ISO (default) to define isotropic expansion.

Set TYPE=ORTHO to define orthotropic expansion.

Set TYPE=ANISO to define fully anisotropic expansion in an ABAQUS/Standard analysis.

Set TYPE=SHORT FIBER to define laminate material properties for each layer in each shell element. This parameter setting is applicable only when using ABAQUS/Standard in conjunction with the ABAQUS Interface for MOLDFLOW. Any data lines given will be ignored. Material properties will be read from the ASCII neutral file identified as jobid.shf. See the ABAQUS Interface for MOLDFLOW User's Manual for more information.

USER

This parameter applies only to ABAQUS/Standard analyses.

Include this parameter to indicate that user subroutine UEXPAN will be used to define increments of thermal strain. The TYPE parameter should be used to indicate the level of anisotropy of thermal expansion. The PORE FLUID parameter can also be used to indicate that the thermal expansion of the pore fluid is being defined.

The DEPENDENCIES and ZERO parameters are not relevant if this parameter is used.

ZERO

If the thermal expansion is temperature- or field-variable-dependent, set this parameter equal to the value of . The default is ZERO=0.

This parameter is not relevant if the USER parameter is included.

Data lines to define isotropic thermal expansion coefficients (TYPE=ISO with USER parameter omitted): 

First line:

  1. . (Units of –1.)

  2. Temperature.

  3. First field variable.

  4. Etc., up to six field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than six):

  1. Seventh field variable.

  2. Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the thermal expansion coefficient as a function of temperature and other predefined field variables.

Data lines to define orthotropic thermal expansion coefficients (TYPE=ORTHO with USER parameter omitted): 

First line:

  1. . (Units of –1.)

  2. .

  3. .

  4. Temperature.

  5. First field variable.

  6. Etc., up to four field variables.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than four):

  1. Fifth field variable.

  2. Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the thermal expansion coefficients as functions of temperature and other predefined field variables.

Data lines to define anisotropic thermal expansion coefficients (TYPE=ANISO with USER parameter omitted): 

First line:

  1. . (Units of –1.)

  2. .

  3. . (Not used for plane stress case.)

  4. .

  5. .

  6. .

  7. Temperature.

  8. First field variable.

Subsequent lines (only needed if the DEPENDENCIES parameter has a value greater than one):

  1. Second field variable.

  2. Etc., up to eight field variables per line.

Repeat this set of data lines as often as necessary to define the thermal expansion coefficients as functions of temperature and other predefined field variables.

To define thermal expansion by a user subroutine (USER parameter included): 

No data lines are used with this option when the USER parameter is specified. Instead, user subroutine UEXPAN must be used to define the thermal expansion (“UEXPAN,” Section 25.2.20 of the ABAQUS Analysis User's Manual).