This option is used to control the calculation of viewfactors during a cavity radiation analysis.
Product: ABAQUS/Standard
Type: History data
Level: Step
Set BLOCKING=ALL (default) to specify that full blocking checks be performed in the viewfactor calculations.
Set BLOCKING=NO to specify that no blocking checks be performed in the viewfactor calculations.
Set BLOCKING=PARTIAL to specify that partial blocking checks be performed in the viewfactor calculations. The data lines are then used to specify the potential blocking surfaces.
Set this parameter equal to the name of the cavity for which radiation viewfactor control is being specified. If this parameter is omitted, the specification applies to all cavities defined in the model.
Include this parameter to switch off cavity radiation effects. Cavity radiation effects can be switched on again by a subsequent use of this option without the OFF parameter. If this parameter is omitted, cavity radiation is active.
Set this parameter equal to a distance beyond which viewfactors need not be calculated because surfaces are judged to be too far apart to “see” each other (due to blocking by other surfaces).
Set REFLECTION=YES (default) to indicate that reflection must be included in the cavity radiation calculations.
Set REFLECTION=NO to indicate that reflection is to be ignored in the cavity radiation calculations. No reflection corresponds to the special case of black body radiation (see “Cavity radiation,” Section 2.11.4 of the ABAQUS Theory Manual).
Include this parameter to indicate the existence of radiation symmetries in the model. This parameter must be set equal to the name appearing in the *RADIATION SYMMETRY option where the symmetries are defined. If this parameter is omitted, it is assumed that there are no radiation symmetries in the cavity.
Set this parameter equal to the acceptable tolerance for the viewfactor calculations. If this parameter is omitted, the default viewfactor tolerance is 0.05.
Set this parameter equal to the maximum allowable motion of any node in the monitored node set before recalculation of radiation viewfactors. This parameter is relevant only when the *MOTION option appears in conjunction with the *RADIATION VIEWFACTOR option. This parameter must be used with the NSET parameter.
Set this parameter equal to the name of the node set whose displacements are to be monitored to decide when geometrical changes are significant enough to trigger recalculation of the radiation viewfactors during the step. This parameter is relevant only when the *MOTION option appears in conjunction with the *RADIATION VIEWFACTOR option. This parameter must be used with the MDISP parameter.