Heat Transfer with Radiation in Participating Media
Use the Heat Transfer with Radiation in Participating Media multiphysics coupling () to account for heat transfer by conduction, convection, and radiation in semitransparent (participating) media. The radiative intensity equations are approximated either by the Discrete Ordinates Method or the P1 Approximation, depending on the Radiation discretization method selected in the Participating Media Settings section of the coupled Radiation in Participating Media interface.
It adds the radiative heat source term Q (SI unit: W/m3) to the heat transfer equation, defined by:
where
•
κ is the absorption coefficient (SI unit: m–1).
•
G is the incident radiation (SI unit: W/m2).
•
Ib(T) is the blackbody radiative intensity (SI unit: W/(m2·sr)), defined as
•
 nr is the refractive index (dimensionless).
•
σ is the Stefan-Boltzmann constant (SI unit: W/(m2·K4)).
•
T is the temperature (SI unit: K)
It also adds the radiative heat flux on boundaries, depending on the selected discretization method. See Opaque Surface (Radiation in Participating Media and Radiation in Absorbing-Scattering Media Interfaces) for the definition of the radiative heat flux.
Settings
The Label is the default multiphysics coupling feature name.
The Name is used primarily as a scope prefix for variables defined by the coupling node. Refer to such variables in expressions using the pattern <name>.<variable_name>. In order to distinguish between variables belonging to different coupling nodes or physics interfaces, the name string must be unique. Only letters, numbers, and underscores (_) are permitted in the Name field. The first character must be a letter.
The default Name (for the first multiphysics coupling feature in the model) is htrpm1.
Coupled Interfaces
This section defines the physics involved in the Heat Transfer with Radiation in Participating Media multiphysics coupling.
Select the Heat transfer interface associated to the temperature dependent variable. Select the Radiation in participating media interface associated to the radiative intensity variable (with Discrete Ordinates Method) or the incident radiation variable (P1 approximation).
In 1D, 1D-axi, and 2D, when the Heat Transfer with Radiation in Participating Media multiphysics coupling is active while solving, it disables all the out of plane features (Out-of-Plane Heat Flux, Out-of-Plane Radiation, Thickness, Cross Section) from the heat transfer interface that is selected in the multiphysics coupling. This is noticed through a warning node displayed under Compile Equations. The radiation interfaces assume an infinite medium in the out-of-plane direction, they are thus not compatible with these features.
Location in User Interface
Context Menus
Multiphysics>Heat Transfer with Radiation in Participating Media
when a Heat Transfer interface or a Slip Flow interface with any domain feature is added together with the Radiation in Participating Media interface with Radiation in Participating Media feature.