Specify distributed surface fluxes for heat transfer analysis.

This option is used to apply distributed surface fluxes for a fully coupled thermal-stress analysis in Abaqus/Standard and Abaqus/Explicit. In Abaqus/Standard it is also used for heat transfer, coupled thermal-electrical, and coupled thermal-electrical-structural analyses.

Related Topics
In Other Guides
Thermal loads


TypeHistory data


Abaqus/CAELoad module

Optional parameters


Set this parameter equal to the name of the amplitude curve that defines the magnitude of the distributed fluxes during the step (Amplitude Curves).

If this parameter is omitted for uniform flux types 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 (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.

For nonuniform flux type SNU (which is available only in Abaqus/Standard), the flux magnitude is defined in user subroutine DFLUX, and AMPLITUDE references are ignored.


Set OP=MOD (default) for existing DSFLUXs to remain, with this option modifying existing fluxes or defining additional fluxes.

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

Data lines to define a distributed surface flux

First line
  1. Surface name.

  2. Distributed flux type label S or SNU.

  3. Reference flux magnitude (units JT−1L−2). This value is needed for uniform fluxes only. If it is given for nonuniform fluxes, it will be passed into user subroutine DFLUX, where the actual flux magnitude is defined.

Repeat this data line as often as necessary to define distributed fluxes for different surfaces.