Diffuse Mirror
This node is a variant of the Diffuse Surface node with a surface emissivity equal to zero. Diffuse mirror surfaces are common as approximations of a surface that is well insulated on one side and for which convection effects can be neglected on the opposite (radiating) side. It resembles a mirror that absorbs all irradiation and then radiates it back in all directions. The node adds radiosity shape function for each spectral band to its selection and uses it as surface radiosity.
The radiative heat flux on a diffuse mirror boundary is zero.
Model Inputs
This section has fields and values that are inputs to expressions that define material properties. If such user-defined property groups have been added, the model inputs are included here.
There is one standard model input — the Temperature T. The default is the temperature variable in the Heat Transfer interface or 293.15 K in the Surface-to-Surface Radiation interface. It is used in the blackbody radiation intensity expression.
Radiation Settings
Select the Radiation direction: Opacity controlled (the default), Negative normal direction, Positive normal direction, or Both sides. For information about these options, see Diffuse Surface.
Ambient
These settings are the same as for the Diffuse Surface node.
Initial Values
These settings are the same as for the Diffuse Surface node.
If this feature is combined with heat transfer in 2D and 1D, the thickness is assumed to be infinite for the view factor computation. The user-defined value for d is still used in the heat transfer equation.
Location in User Interface
Context menus
 Heat Transfer with Surface-to-Surface Radiation>Radiation>Diffuse Mirror
 Surface-to-Surface Radiation>Diffuse Mirror
More locations are available if the Surface-to-surface radiation check box is selected under the Physical Model section. For example:
Heat Transfer in Solids>Radiation>Diffuse Mirror
Ribbon
Physics Tab with Surface-to-Surface Radiation selected:
Boundaries>Surface-to-Surface Radiation>Diffuse Mirror
Physics Tab with Heat Transfer, Heat Transfer in Solids, Heat Transfer in Fluids, Heat Transfer in Porous Media, Heat Transfer in Building Materials, Bioheat Transfer, Heat Transfer with Surface-to-Surface Radiation or Heat Transfer with Radiation in Participating Media selected:
Boundaries>Radiation>Diffuse Mirror