Surface-to-Surface (S2S) Radiation Model Reference

The Surface-to-Surface Radiation model can apply to a multi-part object. Inputs must be specified per-boundary.


Theory	See Theory Guide—S2S (Surface-to-Surface) Radiation.
Provided By	[physics continuum] > Models > Radiation
Example Node Path	Continua > Physics 1 > Models > Surface-to-Surface Radiation
Requires	Space: Three Dimensional Time: Steady or Implicit Unsteady Optional Models: Radiation
Activates	Physics Models	View Factors Radiation Spectrum Solar Radiation
	Boundary Inputs	See S2S Radiation Boundary Settings.
	Region Inputs	See S2S Radiation Region Settings.
	Solvers	See S2S Solvers.
	Field Functions	Boundary Irradiation, Boundary Irradiation on External Side, Boundary Mean Radiant Temperature, Boundary Radiation Heat Flux, Boundary Radiation Heat Flux on External Side, Boundary Radiosity, Boundary Radiosity on External Side, Total Emissivity. See Radiation Field Functions Reference.

The Surface-to-Surface Radiation model is not compatible with the Axisymmetric or Two Dimensional models.

S2S Radiation Boundary Settings

When a simulation uses standard overset mesh with coincident wall boundaries, these boundaries are thermally uncoupled and so can be inconsistent. Decide if the possible errors at the portion of wall with coincident overlapping wall boundaries contribute significantly to the problem of interest. In many cases, the possible errors have very little impact on the problem being studied (for instance on heat transfer toward the body contained within the overset region). If significant error is possible, match the boundary conditions by hand.

Inflow, Outflow, Free Stream, and Wall Boundaries

Radiation Flux Option

This option allows you to model diffuse or directed radiation sources at boundaries according to your own specification. See Diffuse Radiation Flux and Directional Radiation Flux.

Radiation Flux Option	Corresponding Physics Value Nodes
No flux	None
Diffuse radiation flux	Diffuse Radiation Flux The diffuse radiation flux is specified as a scalar profile. Requires the Multiband Thermal Radiation or Gray Thermal Radiation model.
Directional radiation flux	Directional Flux Orientation The direct radiation flux is specified by its direction (default [0.0, 0.0, 1.0]) and the divergence angle of the beam (default zero). Directional Flux Power Distribution The power of the directional flux is specified as a scalar profile. In addition to standard profile methods, a Gaussian method is also available. Requires the Gray or Multiband Thermal Radiation model.

Inflow, Outflow, and Free Stream

Radiation Temperature: The temperature of an open boundary that has a total radiant emittance identical to that of a black body. See Radiation Temperature.

S2S Radiation Region Settings

Radiation Transfer Option

Specifies that a region uses S2S radiation. Either a baffle or porous baffle must be placed between any two regions where only one region has this option activated. This baffle ensures that rays do not pass into regions where S2S is deactivated from regions where it is activated.

Radiation Transfer	Corresponding Physics Value Nodes
Internal Activates S2S transfer at the interior boundaries of the region. Radiation is not explicitly stopped from exiting the region. This depends on whether or not the boundary is defined as transparent (so radiation can exit). This is the default.	None
External Deactivates S2S transfer within the region while boundaries participate in S2S exchange from the external side. Used for opaque regions.	None
Internal and External Boundaries have dual-sided radiation transfer and participate in S2S transfer both internally and externally.	None
None Deactivates S2S transfer for the boundaries of the region.	None

S2S Solver

The S2S solver is activated by default, after Surface-to-Surface Radiation has been selected in the Physics Model Selection dialog and a case geometry has been imported.

The S2S solver has the S2S AMG Linear solver as a sub-solver. See AMG Linear Solver Properties.

注	The S2S solver remains active by default if any continuum using the S2S Radiation model has the Active property On. The S2S solver is halted only when all physics continua with the S2S Radiation model have the Active property switched Off.

Properties

冻结求解器: 开启时，求解器在迭代过程中不更新任何物理量。该选项默认情况下关闭。这是一个调试选项，由于缺少储存，它可能导致不可恢复的错误和错误的求解。有关详细信息，请参见有限体积求解器参考。