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*DFLUX
Specify distributed fluxes in heat transfer, computational fluid dynamics, or mass diffusion analyses.

This option is used to apply distributed fluxes in fully coupled thermal-stress analysis. In Abaqus/Standard it is also used for heat transfer, coupled thermal-electrical, and mass diffusion analyses. In Abaqus/CFD this option is used to specify distributed volumetric heat sources.

Products: Abaqus/Standard  Abaqus/Explicit  Abaqus/CFD  Abaqus/CAE  

Type: History data

Level: Step

Abaqus/CAE: Load module

References:

Optional parameters:

AMPLITUDE

Set this parameter equal to the name of the amplitude curve that defines the magnitude of the distributed fluxes during the step (“Amplitude curves,” Section 34.1.2 of the Abaqus Analysis User's Guide).

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,” Section 6.1.2 of the Abaqus Analysis User's Guide). If this parameter is omitted in an Abaqus/Explicit or Abaqus/CFD analysis, the reference magnitude is applied immediately at the beginning of the step.

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

OP

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

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

Data lines to define a distributed flux: 

First line:

  1. Element number or element set label.

  2. Reference flux magnitude (units of JT–1L–2 for surface fluxes and JT–1L–3 for body fluxes). It is needed for uniform fluxes only. If this value is given for nonuniform fluxes, it will be passed into user subroutine DFLUX, where the actual flux magnitude is defined.

    In heat transfer analysis the units are JT–1L–2 for surface fluxes and JT–1L–3 for body fluxes. In mass diffusion analysis the units are PLT–1 for surface fluxes and PT–1 for body fluxes.

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