tidy3d.RadiationBC

class RadiationBC

Bases: HeatChargeBC

Gray-body surface radiation thermal boundary condition.

Parameters:

• ambient_temperature (PositiveFloat) – [units = K]. Far-field ambient temperature the surface radiates to.

• emissivity (float) – Surface emissivity (dimensionless, between 0 and 1). Must be strictly positive: a zero-emissivity surface exchanges no radiative flux, so the boundary condition would not constrain the temperature.

Notes

The boundary radiates to (and absorbs from) a far-field ambient at ambient_temperature following the Stefan-Boltzmann law

\[q = \varepsilon \sigma \left( T^4 - T_{amb}^4 \right),\]

where \(\varepsilon\) is the surface emissivity and \(\sigma\) the Stefan-Boltzmann constant. This boundary condition is applied by the heat solver (heat and conduction+heat simulations). It is not yet supported in non-isothermal charge (coupled charge+heat) simulations, which reject it at validation.

Example

>>> import tidy3d as td
>>> bc = td.RadiationBC(ambient_temperature=300, emissivity=0.9)

Attributes

ambient_temperature
emissivity

ambient_temperature

emissivity