tidy3d.HeatChargeSimulation

tidy3d.HeatChargeSimulation#

class HeatChargeSimulation[source]#

Bases: AbstractSimulation

Defines thermoelectric simulations.

Parameters:

Notes

A HeatChargeSimulation supports different types of simulations. It solves the heat and conduction equations using the Finite-Volume (FV) method. This solver determines the required computation physics according to the simulation scene definition. This is implemented in this way due to the strong multi-physics coupling.

The HeatChargeSimulation can solve multiple physics and the intention is to enable close thermo-electrical coupling.

Currently, this solver supports steady-state heat conduction where \(q\) is the heat flux, \(k\) is the thermal conductivity, and \(T\) is the temperature.

\[-\nabla \cdot (-k \nabla T) = q\]

It is also possible to run transient heat simulations by specifying analysis_spec=UnsteadyHeatAnalysis(...). This adds the temporal terms to the above equations:

\[\frac{\partial \rho c_p T}{\partial t} -\nabla \cdot (k \nabla(T)) = q\]

where \(\rho\) is the density and \(c_p\) is the specific heat capacity of the medium.

The steady-state electrical Conduction equation depends on the electric conductivity (\(\sigma\)) of a medium, and the electric field (\(\mathbf{E} = -\nabla(\psi)\)) derived from electrical potential (\(\psi\)). Currently, in this type of simulation, no current sources or sinks are supported.

\[\text{div}(\sigma \cdot \nabla(\psi)) = 0\]

For further details on what equations are solved in Charge simulations, refer to the SemiconductorMedium.

Let’s understand how the physics solving is determined:

Simulation Type

Example Configuration Settings

Heat

The heat equation is solved with specified heat sources, boundary conditions, etc. Structures should incorporate materials with defined heat properties.

Conduction

The electrical conduction equation is solved with specified boundary conditions such as VoltageBC, CurrentBC, …

Charge

Drift-diffusion equations are solved for structures containing a defined SemiconductorMedium. Insulators with a ChargeInsulatorMedium can also be included. For these, only the electric potential field is calculated.

Examples

To run a thermal (Heat 🔥) simulation with a solid conductive structure:

>>> import tidy3d as td
>>> heat_sim = td.HeatChargeSimulation(
...     size=(3.0, 3.0, 3.0),
...     structures=[
...         td.Structure(
...             geometry=td.Box(size=(1, 1, 1), center=(0, 0, 0)),
...             medium=td.Medium(
...                 permittivity=2.0,
...                 heat_spec=td.SolidSpec(
...                     conductivity=1,
...                     capacity=1,
...                 )
...             ),
...             name="box",
...         ),
...     ],
...     medium=td.Medium(permittivity=3.0, heat_spec=td.FluidSpec()),
...     grid_spec=td.UniformUnstructuredGrid(dl=0.1),
...     sources=[td.HeatSource(rate=1, structures=["box"])],
...     boundary_spec=[
...         td.HeatChargeBoundarySpec(
...             placement=td.StructureBoundary(structure="box"),
...             condition=td.TemperatureBC(temperature=500),
...         )
...     ],
...     monitors=[td.TemperatureMonitor(size=(1, 2, 3), name="sample", unstructured=True)],
... )

To run a drift-diffusion (Charge ⚡) system:

>>> import tidy3d as td
>>> air = td.FluidMedium(
...     name="air"
... )
>>> intrinsic_Si = td.material_library['cSi'].variants['Si_MultiPhysics'].medium.charge
>>> Si_n = intrinsic_Si.updated_copy(N_d=[td.ConstantDoping(concentration=1e16)], name="Si_n")
>>> Si_p = intrinsic_Si.updated_copy(N_a=[td.ConstantDoping(concentration=1e16)], name="Si_p")
>>> n_side = td.Structure(
...     geometry=td.Box(center=(-0.5, 0, 0), size=(1, 1, 1)),
...     medium=Si_n,
...     name="n_side"
... )
>>> p_side = td.Structure(
...     geometry=td.Box(center=(0.5, 0, 0), size=(1, 1, 1)),
...     medium=Si_p,
...     name="p_side"
... )
>>> bc_v1 = td.HeatChargeBoundarySpec(
...     condition=td.VoltageBC(source=td.DCVoltageSource(voltage=[-1, 0, 0.5])),
...     placement=td.MediumMediumInterface(mediums=[air.name, Si_n.name]),
... )
>>> bc_v2 = td.HeatChargeBoundarySpec(
...     condition=td.VoltageBC(source=td.DCVoltageSource(voltage=0)),
...     placement=td.MediumMediumInterface(mediums=[air.name, Si_p.name]),
... )
>>> charge_sim = td.HeatChargeSimulation(
...     structures=[n_side, p_side],
...     medium=td.Medium(heat_spec=td.FluidSpec(), name="air"),
...     monitors=[td.SteadyFreeCarrierMonitor(
...         center=(0, 0, 0), size=(td.inf, td.inf, 0), name="charge_mnt", unstructured=True
...     )],
...     center=(0, 0, 0),
...     size=(3, 3, 3),
...     grid_spec=td.UniformUnstructuredGrid(dl=0.05),
...     boundary_spec=[bc_v1, bc_v2],
...     analysis_spec=td.IsothermalSteadyChargeDCAnalysis(
...         tolerance_settings=td.ChargeToleranceSpec(rel_tol=1e5, abs_tol=3e3, max_iters=400),
...         convergence_dv=10),
...     )

Coupling between Heat and electrical Conduction simulations is currently limited to 1-way. This is specified by defining a heat source of type HeatFromElectricSource. With this coupling, joule heating is calculated as part of the solution to a Conduction simulation and translated into the Heat simulation.

Two common scenarios can use this coupling definition:
  1. One in which BCs and sources are specified for both Heat and Conduction simulations.

    In this case one mesh will be generated and used for both the Conduction and Heat simulations.

  2. Only heat BCs/sources are provided. In this case, only the Heat equation will be solved.

    Before the simulation starts, it will try to load the heat source from file so a previously run Conduction simulations must have run previously. Since the Conduction and Heat meshes may differ, an interpolation between them will be performed prior to starting the Heat simulation.

Additional heat sources can be defined, in which case, they will be added on top of the coupling heat source.

Attributes

medium

Background medium of simulation, defaults to a standard dispersion-less Medium if not specified.

sources

monitors

boundary_spec

grid_spec

symmetry

analysis_spec

structures

Tuple of structures present in simulation.

version

plot_length_units

structure_priority_mode

Validating setup

size

center

Methods

from_scene(scene, **kwargs)

Create a simulation from a Scene instance.

plot([x, y, z, ax, source_alpha, ...])

Plot each of simulation's components on a plane defined by one nonzero x,y,z coordinate.

plot_boundaries([x, y, z, property, ax])

Plot each of simulation's boundary conditions on a plane defined by one nonzero x,y,z coordinate.

plot_heat_conductivity([x, y, z, ax, alpha, ...])

DEPRECATED: Method added for backwards compatibility with HeatSimulation.plot_heat_conductivity.

plot_property([x, y, z, ax, alpha, ...])

Plot each of simulation's components on a plane defined by one nonzero x,y,z coordinate.

plot_sources([x, y, z, property, hlim, ...])

Plot each of simulation's sources on a plane defined by one nonzero x,y,z coordinate.

source_bounds([property])

Compute range of heat sources present in the simulation.
medium#

Background medium of simulation, defaults to a standard dispersion-less Medium if not specified.

sources#
monitors#
boundary_spec#
grid_spec#
symmetry#
analysis_spec#
plot(x=None, y=None, z=None, ax=None, source_alpha=None, monitor_alpha=None, hlim=None, vlim=None, fill_structures=True, **patch_kwargs)[source]#

Plot each of simulation’s components on a plane defined by one nonzero x,y,z coordinate.

Parameters:

  • x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

  • y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

  • z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

  • ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

  • source_alpha (float = None) – Opacity of the sources. If None, uses Tidy3d default.

  • monitor_alpha (float = None) – Opacity of the monitors. If None, uses Tidy3d default.

  • hlim (Tuple[float, float] = None) – The x range if plotting on xy or xz planes, y range if plotting on yz plane.

  • vlim (Tuple[float, float] = None) – The z range if plotting on xz or yz planes, y plane if plotting on xy plane.

  • fill_structures (bool = True) – Whether to fill structures with color or just draw outlines.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_property(x=None, y=None, z=None, ax=None, alpha=None, source_alpha=None, monitor_alpha=None, property='heat_conductivity', hlim=None, vlim=None)[source]#

Plot each of simulation’s components on a plane defined by one nonzero x,y,z coordinate.

Parameters:

  • x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

  • y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

  • z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

  • ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

  • alpha (float = None) – Opacity of the structures being plotted. Defaults to the structure default alpha.

  • source_alpha (float = None) – Opacity of the sources. If None, uses Tidy3d default.

  • monitor_alpha (float = None) – Opacity of the monitors. If None, uses Tidy3d default.

  • property (str = "heat_conductivity") – Specified the type of simulation for which the plot will be tailored. Options are [“heat_conductivity”, “electric_conductivity”, “source”]

  • hlim (tuple[float, float] = None) – The x range if plotting on xy or xz planes, y range if plotting on yz plane.

  • vlim (tuple[float, float] = None) – The z range if plotting on xz or yz planes, y plane if plotting on xy plane.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_heat_conductivity(x=None, y=None, z=None, ax=None, alpha=None, source_alpha=None, monitor_alpha=None, colorbar='conductivity', hlim=None, vlim=None, **kwargs)[source]#

DEPRECATED: Method added for backwards compatibility with HeatSimulation.plot_heat_conductivity. Plot each of simulation’s components on a plane defined by one nonzero x,y,z coordinate.

Parameters:

  • x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

  • y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

  • z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

  • ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

  • alpha (float = None) – Opacity of the structures being plotted. Defaults to the structure default alpha.

  • source_alpha (float = None) – Opacity of the sources. If None, uses Tidy3d default.

  • monitor_alpha (float = None) – Opacity of the monitors. If None, uses Tidy3d default.

  • colorbar (str = "conductivity") – Display colorbar for thermal conductivity (“conductivity”) or heat source rate (“source”).

  • hlim (tuple[float, float] = None) – The x range if plotting on xy or xz planes, y range if plotting on yz plane.

  • vlim (tuple[float, float] = None) – The z range if plotting on xz or yz planes, y plane if plotting on xy plane.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_boundaries(x=None, y=None, z=None, property='heat_conductivity', ax=None)[source]#

Plot each of simulation’s boundary conditions on a plane defined by one nonzero x,y,z coordinate.

Parameters:

  • x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

  • y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

  • z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

  • property (str = None) – Specified the type of simulation for which the plot will be tailored. Options are [“heat_conductivity”, “electric_conductivity”]

  • ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

plot_sources(x=None, y=None, z=None, property='heat_conductivity', hlim=None, vlim=None, alpha=None, ax=None)[source]#

Plot each of simulation’s sources on a plane defined by one nonzero x,y,z coordinate.

Parameters:

  • x (float = None) – position of plane in x direction, only one of x, y, z must be specified to define plane.

  • y (float = None) – position of plane in y direction, only one of x, y, z must be specified to define plane.

  • z (float = None) – position of plane in z direction, only one of x, y, z must be specified to define plane.

  • property (str = None) – Specified the type of simulation for which the plot will be tailored. Options are [“heat_conductivity”, “electric_conductivity”]

  • hlim (tuple[float, float] = None) – The x range if plotting on xy or xz planes, y range if plotting on yz plane.

  • vlim (tuple[float, float] = None) – The z range if plotting on xz or yz planes, y plane if plotting on xy plane.

  • alpha (float = None) – Opacity of the sources, If None uses Tidy3d default.

  • ax (matplotlib.axes._subplots.Axes = None) – Matplotlib axes to plot on, if not specified, one is created.

Returns:

The supplied or created matplotlib axes.

Return type:

matplotlib.axes._subplots.Axes

source_bounds(property='heat_conductivity')[source]#

Compute range of heat sources present in the simulation.

classmethod from_scene(scene, **kwargs)[source]#

Create a simulation from a Scene instance. Must provide additional parameters to define a valid simulation (for example, size, grid_spec, etc).

Parameters:

  • scene (Scene) – Scene containing structures information.

  • **kwargs – Other arguments

Example

>>> from tidy3d import Scene, Medium, Box, Structure, UniformUnstructuredGrid, TemperatureMonitor
>>> box = Structure(
...     geometry=Box(center=(0, 0, 0), size=(1, 2, 3)),
...     medium=Medium(permittivity=5),
...     name="box"
... )
>>> scene = Scene(
...     structures=[box],
...     medium=Medium(
...         permittivity=3,
...         heat_spec=SolidMedium(
...             conductivity=1, capacity=1,
...         ),
...     ),
... )
>>> sim = HeatChargeSimulation.from_scene(
...     scene=scene,
...     center=(0, 0, 0),
...     size=(5, 6, 7),
...     grid_spec=UniformUnstructuredGrid(dl=0.4),
...     boundary_spec=[
...         HeatChargeBoundarySpec(
...             placement=StructureBoundary(structure="box"),
...             condition=TemperatureBC(temperature=500),
...         )
...     ],
...     monitors=[TemperatureMonitor(name="temp_monitor", center=(0, 0, 0), size=(1, 1, 1), unstructured=True)],
... )