Symmetry

The Symmetry node provides a boundary condition for symmetry boundaries. This boundary condition is similar to an insulation condition, and it means that there is no heat flux across the boundary.

B O U N D A R Y S E L E C T I O N

In most cases, the Symmetry node does not require any user input. If

required, define the symmetry boundaries.

Note

Heat Flux

Use the Heat Flux node to add heat flux across boundaries. A positive heat flux adds heat to the domain. This feature is not applicable to inlet boundaries.

B O U N D A R Y S E L E C T I O N

From the Selection list, choose the boundaries to add the heat flux contribution.

P A I R S E L E C T I O N

If Heat Flux is selected from the Pairs menu, choose the pair to define. An identity pair has to be created first. Ctrl-click to deselect.

H E A T F L U X

Click one of the General inward heat flux, Inward heat flux, or Total heat flux buttons.

•If General inward heat flux q0 (SI unit: W/m2) is selected, it adds to the total flux across the selected boundaries. Enter a value for q0 to represent a heat flux that enters the domain. For example, any electric heater is well represented by this

condition, and its geometry can be omitted.

•If Inward heat flux is selected, enter the Heat transfer coefficient h (SI unit: W/ (m2·K). The default is 0. Also enter an External temperature Text (SI unit: K). The default is 293.15 K. The value depends on the geometry and the ambient flow

conditions. Inward heat flux is defined by this equation:

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