*SRADIATE

Specify surface radiation conditions in heat transfer analysis.

This option is used to apply surface radiation boundary conditions between a nonconcave surface and a nonreflecting environment in fully coupled thermal-stress analysis or to define an approximate cavity radiation interaction. In Abaqus/Standard it is also used for all procedures that solve for nodal temperature degrees of freedom.

It must be used in conjunction with the PHYSICAL CONSTANTS option, which is used to define the Stefan-Boltzmann constant.

This page discusses:

See Also
In Other Guides
Thermal Loads
Cavity Radiation in Abaqus/Standard

Products Abaqus/Standard Abaqus/Explicit Abaqus/CAE

Type History data

LevelStep

Abaqus/CAE Interaction module

Optional parameters

AMBIENT AMPLITUDE

Set this parameter equal to the name of the AMPLITUDE option that gives the variation of the ambient temperature with time.

If this parameter is omitted in an Abaqus/Standard analysis, the reference magnitude is applied immediately at the beginning of the step or linearly over the step, depending on the value assigned to the AMPLITUDE parameter on the STEP option (see Defining an Analysis). If this parameter is omitted in an Abaqus/Explicit analysis, the reference magnitude is applied immediately at the beginning of the step.

OP

Set OP=MOD (default) for existing SRADIATE definitions to remain, with this option modifying existing radiation conditions or defining additional radiation conditions.

Set OP=NEW if all existing SRADIATE definitions applied to the model should be removed.

RADIATION AMPLITUDE

Set this parameter equal to the name of the AMPLITUDE option that gives the variation of the total radiation flux with time.

If this parameter is omitted in an Abaqus/Standard analysis, the total radiation flux, accounting for any AMBIENT AMPLITUDE, is applied immediately, independent of the value assigned to the AMPLITUDE parameter on the STEP option. If this parameter is omitted in an Abaqus/Explicit analysis, the total radiation flux, accounting for any AMBIENT AMPLITUDE, is applied immediately at the beginning of the step.

Data lines to define surface radiation conditions

First line

  1. Surface name.

  2. Radiation type label R.

  3. Reference ambient temperature value, θ 0 . (Units of θ .)

  4. Emissivity, ϵ .

Repeat this data line as often as necessary to define radiation conditions for different surfaces.

Data lines to define approximate cavity radiation (available only in Abaqus/Standard)

First line

  1. Surface name.

  2. Radiation type label AVG.

  3. Leave this field blank.

  4. Emissivity, ϵ .

Repeat this data line as often as necessary to define radiation conditions for different surfaces.