where ε is the surface emissivity,
σ is the Stefan-Boltzmann constant (a predefined physical constant), and
Tamb is the ambient temperature.
This section is available when temperature-dependent material properties are used. By default, the temperature of the parent interface is used and the section is not editable. To edit the Temperature field, click
Make All Model Inputs Editable (
). The available options are
User defined (default),
Common model input (the
minput.T variable, set to 293.15 K by default), and all temperature variables from the physics interfaces included in the model. To edit the
minput.T variable, click the
Go to Source button (
), and in the
Default Model Inputs node under
Global Definitions, set a value for the
Temperature in the
Expression for remaining selection section.
Define on which side of the boundary is the ambient domain that receives the radiation, by selecting a Radiation direction:
Upside or
Downside. This setting has no effect unless the temperature differs from one side of the boundary to the other.
The default Surface emissivity ε (a dimensionless number between 0 and 1) is taken
From material. For
User defined, it should be specified. An emissivity of 0 means that the surface emits no radiation at all while an emissivity of 1 means that it is a perfect blackbody.
For User defined, enter an
Ambient temperature Tamb. The default value is approximately room temperature, 293.15 K (20ºC). Else, select an
Ambient temperature defined in an
Ambient Properties node under
Definitions>Shared Properties.
