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*KAPPA
Specify the material parameters for mass diffusion driven by gradients of temperature and equivalent pressure stress.

This option is used to introduce temperature- and pressure-driven mass diffusion using the material parameters and , respectively. It must appear immediately after the *DIFFUSIVITY option. For each use of the *DIFFUSIVITY option, *KAPPA can be used once with TYPE=TEMP and once with TYPE=PRESS. The *KAPPA, TYPE=TEMP and *DIFFUSIVITY, LAW=FICK options are mutually exclusive.

Products: Abaqus/Standard  Abaqus/CAE  

Type: Model data

Level: Model  

Abaqus/CAE: Property module

References:

Optional parameters:

DEPENDENCIES

Set this parameter equal to the number of field variables included in the definition of or . If this parameter is omitted, or is assumed not to depend on any field variables but may still depend on concentration and temperature. See “Specifying field variable dependence” in “Material data definition,” Section 21.1.2 of the Abaqus Analysis User's Guide, for more information.

TYPE

Set TYPE=TEMP (default) to define (governing mass diffusion caused by temperature gradients). Set TYPE=PRESS to define (governing mass diffusion caused by gradients of the equivalent pressure stress).

Data lines to define the Soret effect factor (TYPE=TEMP): 

First line:

  1. Soret effect factor, . (Units of F1/2L–1.)

  2. Concentration, c.

  3. Temperature, .

  4. First field variable.

  5. Second field variable.

  6. Etc., up to five field variables.

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

  1. Sixth field variable.

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

Repeat this set of data lines as often as necessary to define as a function of concentration, temperature, and other predefined field variables.

Data lines to define the pressure stress factor (TYPE=PRESS): 

First line:

  1. Pressure stress factor, . (Units of LF–1/2.)

  2. Concentration, c.

  3. Temperature, .

  4. First field variable.

  5. Second field variable.

  6. Etc., up to five field variables.

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

  1. Sixth field variable.

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

Repeat this set of data lines as often as necessary to define as a function of concentration, temperature, and other predefined field variables.