Open Boundary

The Open Boundary node adds a boundary condition for modeling heat flux across an open boundary: the heat can flow out of the domain or into the domain with a specified exterior temperature. Use an Open Boundary node to limit a modeling domain that extends in an open fashion.

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 model as open boundaries.

E X T E R I O R T E M P E R A T U R E

Enter the exterior Temperature T0 (SI unit: K) outside of the open boundary.

Periodic Heat Condition

Use the Periodic Heat Condition node to add a periodic heat condition to boundaries. Right-click the node to add a Destination Selection feature.

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 a periodic heat condition.

Surface-to-Ambient Radiation

Use the Surface-to-Ambient Radiation boundary condition to add surface-to-ambient radiation to boundaries. The net inward heat flux from surface-to-ambient radiation is

q = T4amb – T4

where is the surface emissivity, is the Stefan-Boltzmann constant (a predefined physical constant), and Tamb is the ambient temperature.

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 surface-to-ambient radiation contribution.

S U R F A C E - T O - A M B I E N T R A D I A T I O N

The default Surface emissivity e (a dimensionless number between 0 and 1) is taken From material. An emissivity of 0 means that the surface emits no radiation at all and an emissivity of 1 means that it is a perfect blackbody. Enter an Ambient temperature Tamb (SI unit: K). The default is 293.15 K.

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