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 material properties are temperature-dependent. 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.
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.
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.
Physics tab with interface as
Heat Transfer in Solids or any version of the Heat Transfer interface selected:
Physics tab with Porous Medium>Fluid or
Porous Medium>Porous Matrix selected in the model tree: