tidy3d.ThermalContactResistance

class ThermalContactResistance

Bases: HeatChargeBC

Interfacial thermal resistance (thermal contact / Kapitza resistance) between two touching solids.

Parameters:

resistance (PositiveFloat) – [units = K*um^2/W]. Interfacial thermal resistance in units of K*um^2/W.

Notes

The interface transmits the heat flux

\[q'' = \frac{1}{R} \left( T_1 - T_2 \right),\]

so the temperature is discontinuous across the interface: the temperature jump is proportional to the heat flux crossing it. This models thin thermally-resistive interfaces (imperfect bonding, grain boundaries, phonon mismatch between thin films) without meshing them. This condition can only be placed on an interface between two solids (StructureStructureInterface or MediumMediumInterface).

This boundary condition is applied by the heat solver, including when heat is coupled with electrical conduction. It is not supported in non-isothermal charge (coupled charge+heat) simulations, where the coupled thermal solve does not apply the interfacial thermal resistance, so including it there raises a setup error.

Example

>>> import tidy3d as td
>>> bc = td.ThermalContactResistance(resistance=3e3)  # K*um^2/W
>>> bc_si = td.ThermalContactResistance.from_si_units(resistance=3e-9)  # m^2*K/W

Attributes

resistance

Methods

from_si_units(resistance)

Create a ThermalContactResistance using SI units.

resistance

classmethod from_si_units(resistance)

Create a ThermalContactResistance using SI units.

Args:

resistance: Interfacial thermal resistance in [m^2*K/W].

Returns:

An instance of ThermalContactResistance with the value converted to Tidy3D’s internal unit system.