FESTIM v0.8
import FESTIM as F
parameters = {
"mesh_parameters": {
"vertices": [0, 1, 2, 3, 4]
},
"materials": [
{
"id": 1,
"D_0": 4.1e-9,
"E_D": 0.3
},
{
"id": 2,
"D_0": 8.7e-9,
"E_D": 0.4
}
],
"boundary_conditions": [
{
"type": "dc",
"surfaces": [1, 2],
"value": 2
}
],
"temperature": {
"type": "expression",
"value": 2*F.x + F.t
},
"source_term": {
"value": 1
},
"solving_parameters": {
"absolute_tolerance": 1e-10,
"relative_tolerance": 1e-10,
"maximum_iterations": 50,
"final_time": 10,
"initial_stepsize": 0.1
}
}
F.run(parameters)
import FESTIM as F
my_sim = F.Simulation()
my_sim.mesh = F.MeshFromVertices([0, 1, 2, 3, 4])
tungsten = F.Material(id=1, D_0=4.1e-9, E_D=0.3)
copper = F.Material(id=2, D_0=8e-7, E_D=0.4)
my_sim.materials = F.Materials(
[tungsten, copper]
)
my_sim.boundary_conditions = [
F.DirichletBC(surfaces=[1, 2], value=2)
]
my_sim.T = F.Temperature(2*F.x + F.t)
my_sim.sources = F.Source(1, volumes=1, field="solute")
my_sim.settings = F.Settings(
absolute_tolerance=1e-10,
relative_tolerance=1e-10,
maximum_iterations=50,
transient=True,
final_time=10
)
my_sim.dt= F.Stepsize(0.1)
my_sim.initialise()
my_sim.run()
FESTIM 0.8
FESTIM 0.7
class Trap(F.Concentration):
def __init__(
self, k_0, E_k, p_0, E_p, materials, density, id=None):
Easy to document
Easy to document
class Trap(F.Concentration):
def __init__(
self, k_0, E_k, p_0, E_p, materials, density, id=None):
"""Inits Trap
Args:
k_0 (float): trapping pre-exponential factor
E_k (float): trapping activation energy
p_0 (float): detrapping pre-exponential factor
E_p (float): detrapping activation energy
materials (list or int): the materials ids the trap is living in
density (sp.Add, float): the trap density
id (int, optional): The trap id. Defaults to None.
Raises:
ValueError: if duplicates are found in materials
"""
Easy to extend
class CustomSource(F.Source):
def __init__(self, A, B, volume):
value = A*F.t + B*(F.x + F.y**2)
super().__init__(value, volume, field="solute")
my_source = CustomSource(A=2, B=4, volume=1)
class Stepsize:
def adapt(self, t, nb_it, converged):
"""Changes the stepsize based on convergence.
Args:
t (float): current time.
nb_it (int): number of iterations the solver required to converge.
converged (bool): True if the solver converged, else False.
"""
change_ratio = self.adaptive_stepsize["stepsize_change_ratio"]
dt_min = self.adaptive_stepsize["dt_min"]
stepsize_stop_max = self.adaptive_stepsize["stepsize_stop_max"]
t_stop = self.adaptive_stepsize["t_stop"]
if not converged:
self.value.assign(float(self.value)/change_ratio)
if float(self.value) < dt_min:
raise ValueError('stepsize reached minimal value')
if nb_it < 5:
self.value.assign(float(self.value)*change_ratio)
else:
self.value.assign(float(self.value)/change_ratio)
if t_stop is not None:
if t >= t_stop:
if float(self.value) > stepsize_stop_max:
self.value.assign(stepsize_stop_max)
class Stepsize:
def adapt(self, t, nb_it, converged):
"""Changes the stepsize based on convergence.
Args:
t (float): current time.
nb_it (int): number of iterations the solver required to converge.
converged (bool): True if the solver converged, else False.
"""
change_ratio = self.adaptive_stepsize["stepsize_change_ratio"]
dt_min = self.adaptive_stepsize["dt_min"]
stepsize_stop_max = self.adaptive_stepsize["stepsize_stop_max"]
t_stop = self.adaptive_stepsize["t_stop"]
if not converged:
self.value.assign(float(self.value)/change_ratio)
if float(self.value) < dt_min:
raise ValueError('stepsize reached minimal value')
if nb_it < 5:
self.value.assign(float(self.value)*change_ratio)
else:
self.value.assign(float(self.value)/change_ratio)
if t_stop is not None:
if t >= t_stop:
if float(self.value) > stepsize_stop_max:
self.value.assign(stepsize_stop_max)
class CustomSource(F.Source):
def __init__(self, A, B, volume):
value = A*F.t + B*(F.x + F.y**2)
super().__init__(value, volume, field="solute")
my_source = CustomSource(A=2, B=4, volume=1)
Easy to extend
class CustomStepsize(F.Stepsize):
def adapt(self, t, nb_it, converged):
Inheritance
Easy to extend
class CustomStepsize(F.Stepsize):
def adapt(self, t, nb_it, converged):
print('Adapting stepsize')
if converged:
self.value *= 1.2 * (1 - nb_it/5)
else:
self.value *= 1/2
class RecombinationFlux(F.SurfaceFlux):
def __init__(self, Kr_0, E_Kr, surface):
super().__init__(field="solute", surface=surface)
self.Kr_0 = Kr_0
self.E_Kr = E_Kr
def compute(self):
Kr = self.Kr_0*exp(-self.E_Kr/F.k_B/self.T)
return Kr*self.function**2
class MobileTrap(F.Trap):
def create_form(self, **kwargs):
super().create_form(**kwargs)
self.F += 2 * dot(
grad(self.solution), grad(self.test_function))*kwargs["dx"]
class LinearMesh(F.MeshFromVertices):
def __init__(self, N, start_dx, ratio):
dx = np.empty((N,))
dx[0] = start_dx
dx[1:] = ratio
dx = np.cumprod(dx)
vertices = np.concatenate([0], np.cumsum(dx))
super().create_form(vertices)
Inheritance
Override methods
Easy to extend
class CustomStepsize(F.Stepsize):
def adapt(self, t, nb_it, converged):
print('Adapting stepsize')
if converged:
self.value *= 1.2 * (1 - nb_it/5)
else:
self.value *= 1/2
class RecombinationFlux(F.SurfaceFlux):
def __init__(self, Kr_0, E_Kr, surface):
super().__init__(field="solute", surface=surface)
self.Kr_0 = Kr_0
self.E_Kr = E_Kr
def compute(self):
Kr = self.Kr_0*exp(-self.E_Kr/F.k_B/self.T)
return Kr*self.function**2
class MobileTrap(F.Trap):
def create_form(self, **kwargs):
super().create_form(**kwargs)
self.F += 2 * dot(
grad(self.solution), grad(self.test_function))*kwargs["dx"]
class LinearMesh(F.MeshFromVertices):
def __init__(self, N, start_dx, ratio):
dx = np.empty((N,))
dx[0] = start_dx
dx[1:] = ratio
dx = np.cumprod(dx)
vertices = np.concatenate([0], np.cumsum(dx))
super().create_form(vertices)
Easy to extend
Easy to read
10 files
FESTIM 0.7
47 files
FESTIM 0.8
\approx 138 \; \mathrm{lines/file}
\approx 32 \; \mathrm{lines/file}
10 files
FESTIM 0.7
47 files
FESTIM 0.8
\approx 138 \; \mathrm{lines/file}
\approx 32 \; \mathrm{lines/file}
Easy to read
10 files
FESTIM 0.7
47 files
FESTIM 0.8
\approx 138 \; \mathrm{lines/file}
\approx 32 \; \mathrm{lines/file}
Easy to read
Easy to
test
Smaller portions of code
=
Smaller tests
=
Better tests
Usage
Meshes
my_sim.mesh = my_mesh
Meshes
my_mesh = MeshFromVertices([0, 1, 2, 3, 4])
my_sim.mesh = my_mesh
Meshes
my_mesh = MeshFromRefinements(
initial_number_of_cells=10,
size=1,
refinements=[{
"x": 0.5, "cells": 10
}]
)
my_sim.mesh = my_mesh
Meshes
my_mesh = MeshFromXDMF(
volume_file="mesh.xdmf",
boundary_file="boundaries.xdmf"
)
my_sim.mesh = my_mesh
Materials
my_sim.materials = my_materials
Materials
tungsten = F.Material(id=1, D_0=1, E_D=0.1)
copper = F.Material(id=2, D_0=2, E_D=0.2)
my_sim.materials = my_materials
Materials
tungsten = F.Material(id=1, D_0=1, E_D=0.1)
copper = F.Material(id=2, D_0=2, E_D=0.2)
my_materials = F.Materials([
tungsten,
copper,
])
my_sim.materials = my_materials
Traps
my_sim.traps = ...
Traps
trap1 = F.Trap(k_0=1, E_k=0.1, p_0=2, E_p=0.8, materials=[1, 2], density=10)
trap2 = F.Trap(k_0=1, E_k=0.1, p_0=3, E_p=1, materials=[1], density=1)
my_sim.traps = [trap1, trap2]
- Trap
Traps
trap1 = F.Trap(k_0=1, E_k=0.1, p_0=2, E_p=0.8, materials=[1, 2], density=10)
trap2 = F.Trap(k_0=1, E_k=0.1, p_0=3, E_p=1, materials=[1], density=1)
trap3 = F.ExtrinsicTrap(
k_0=1, E_k=0.1, p_0=3, E_p=1, materials=[1],
form_parameters=...
)
my_sim.traps = [trap1, trap2, trap3]
- Trap
- ExtrinsicTrap
Traps
trap1 = F.Trap(k_0=1, E_k=0.1, p_0=2, E_p=0.8, materials=[1, 2], density=10)
trap2 = F.Trap(k_0=1, E_k=0.1, p_0=3, E_p=1, materials=[1], density=1)
trap3 = F.ExtrinsicTrap(
k_0=1, E_k=0.1, p_0=3, E_p=1, materials=[1],
form_parameters=...
)
my_sim.traps = [trap1, trap2, trap3]
- Trap
- ExtrinsicTrap
- NeutronInducedTrap?
Exports
my_sim.exports = F.Exports(list_of_exports)
Exports
list_of_exports = [
F.TXTExport("solute", times=[10, 100], label="mobile", folder="out"),
]
my_sim.exports = F.Exports(list_of_exports)
Exports
list_of_exports = [
F.TXTExport("solute", times=[10, 100], label="mobile", folder="out"),
F.XDMFExport("retention", label="retention", folder="out"),
]
my_sim.exports = F.Exports(list_of_exports)
Exports
list_of_exports = [
F.TXTExport("solute", times=[10, 100], label="mobile", folder="out"),
F.XDMFExport("retention", label="retention", folder="out"),
derived_quantities
]
my_sim.exports = F.Exports(list_of_exports)
Exports
derived_quantities = F.DerivedQuantities(
[
F.AverageVolume("retention", volume=1)
]
)
list_of_exports = [
F.TXTExport("solute", times=[10, 100], label="mobile", folder="out"),
F.XDMFExport("retention", label="retention", folder="out"),
derived_quantities
]
my_sim.exports = F.Exports(list_of_exports)
Exports
derived_quantities = F.DerivedQuantities(
[
F.AverageVolume("retention", volume=1),
F.HydrogenFlux(surface=2)
]
)
list_of_exports = [
F.TXTExport("solute", times=[10, 100], label="mobile", folder="out"),
F.XDMFExport("retention", label="retention", folder="out"),
derived_quantities
]
my_sim.exports = F.Exports(list_of_exports)
Exports
derived_quantities = F.DerivedQuantities(
[
F.AverageVolume("retention", volume=1),
F.HydrogenFlux(surface=2),
F.ThermalFlux(surface=[1, 2])
]
)
list_of_exports = [
F.TXTExport("solute", times=[10, 100], label="mobile", folder="out"),
F.XDMFExport("retention", label="retention", folder="out"),
derived_quantities
]
my_sim.exports = F.Exports(list_of_exports)
Boundary Conditions
my_sim.boundary_conditions = list_of_bcs
Boundary Conditions
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
Boundary Conditions
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5)
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
Boundary Conditions
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5),
F.ImplantationDirichlet(surfaces=4, phi=10, R_p=5e-9, D_0=1, E_D=0.1)
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
- ImplantationDirichlet
Boundary Conditions
def bc(T, cm, K):
return K*T*cm
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5),
F.ImplantationDirichlet(surfaces=4, phi=10, R_p=5e-9, D_0=1, E_D=0.1)
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
- ImplantationDirichlet
Boundary Conditions
def bc(T, cm, K):
return K*T*cm
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5),
F.ImplantationDirichlet(surfaces=4, phi=10, R_p=5e-9, D_0=1, E_D=0.1),
F.CustomDirichlet(surfaces=5, function=bc, component="solute", K=2*F.t)
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
- ImplantationDirichlet
- CustomDirichlet
Boundary Conditions
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5),
F.ImplantationDirichlet(surfaces=4, phi=10, R_p=5e-9, D_0=1, E_D=0.1),
F.CustomDirichlet(surfaces=5, function=bc, component="solute", K=2*F.t),
F.ConvectiveFlux(surfaces=6, h_coeff=10, T_ext=350)
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
- ImplantationDirichlet
- CustomDirichlet
- ConvectiveFlux
Boundary Conditions
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5),
F.ImplantationDirichlet(surfaces=4, phi=10, R_p=5e-9, D_0=1, E_D=0.1),
F.CustomDirichlet(surfaces=5, function=bc, component="solute", K=2*F.t),
F.ConvectiveFlux(surfaces=6, h_coeff=10, T_ext=350),
F.RecombinationFlux(surfaces=7, Kr_0=10, E_Kr=0.1, order=2)
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
- ImplantationDirichlet
- CustomDirichlet
- ConvectiveFlux
- RecombinationFlux
Boundary Conditions
list_of_bcs = [
F.DirichletBC(surfaces=1, value=10, component="T"),
F.SievertsBC(surfaces=[2, 3], S_0=100, E_S=0.1, pressure=1e5),
F.ImplantationDirichlet(surfaces=4, phi=10, R_p=5e-9, D_0=1, E_D=0.1),
F.CustomDirichlet(surfaces=5, function=bc, component="solute", K=2*F.t),
F.ConvectiveFlux(surfaces=6, h_coeff=10, T_ext=350),
F.RecombinationFlux(surfaces=7, Kr_0=10, E_Kr=0.1, order=2),
F.FluxBC(surfaces=8, value=10 + sp.sin(F.t), component="solute")
]
my_sim.boundary_conditions = list_of_bcs
- DirichletBC
- SievertsBC
- ImplantationDirichlet
- CustomDirichlet
- ConvectiveFlux
- RecombinationFlux
- FluxBC
Temperature
my_sim.T = my_temperature
Temperature
my_temperature = F.Temperature(350)
my_sim.T = my_temperature
- Temperature (expression)
Temperature
my_temperature = F.HeatTransferProblem(transient=True, initial_value=350)
my_sim.T = my_temperature
- Temperature (expression)
- HeatTransferProblem
Settings
my_sim.settings = my_settings
Settings
my_settings = F.Settings(
absolute_tolerance=1e10,
relative_tolerance=1e-10,
)
my_sim.settings = my_settings
Many parameters have default values
Settings
my_settings = F.Settings(
absolute_tolerance=1e10,
relative_tolerance=1e-10,
maximum_iterations=30,
transient=True,
final_time=10,
chemical_pot=False,
soret=False,
traps_element_type="CG",
update_jacobian=True,
completion_tone=False
)
my_sim.settings = my_settings
def __init__(
self,
absolute_tolerance,
relative_tolerance,
maximum_iterations=30,
transient=True,
final_time=None,
chemical_pot=False,
soret=False,
traps_element_type="CG",
update_jacobian=True,
completion_tone=False
):
"""Inits Settings
Args:
absolute_tolerance (float): the absolute tolerance of the newton
solver
relative_tolerance (float): the relative tolerance of the newton
solver
maximum_iterations (int, optional): maximum iterations allowed for
the solver to converge. Defaults to 30.
transient (bool, optional): If set to True, the simulation will be
transient. Defaults to True.
final_time (float, optional): final time of the simulation.
Defaults to None.
chemical_pot (bool, optional): if True, conservation of chemical
potential will be assumed. Defaults to False.
soret (bool, optional): if True, Soret effect will be assumed.
Defaults to False.
traps_element_type (str, optional): Finite element used for traps.
If traps densities are discontinuous (eg. different materials)
"DG" is recommended. Defaults to "CG".
update_jacobian (bool, optional): If set to False, the Jacobian of
the formulation will be computed only once at the beggining.
Else it will be computed at each time step. Defaults to True.
completion_tone (bool, optional): If True, a native os alert
tone will alert user upon completion of current run. Defaults
to False.
"""
Everything is documented
Settings
my_settings = F.Settings(
absolute_tolerance=1e10,
relative_tolerance=1e-10,
maximum_iterations=30,
transient=True,
final_time=10,
chemical_pot=False,
soret=False,
traps_element_type="CG",
update_jacobian=True,
completion_tone=False
)
my_sim.settings = my_settings
def __init__(
self,
absolute_tolerance,
relative_tolerance,
maximum_iterations=30,
transient=True,
final_time=None,
chemical_pot=False,
soret=False,
traps_element_type="CG",
update_jacobian=True,
completion_tone=False
):
"""Inits Settings
Args:
absolute_tolerance (float): the absolute tolerance of the newton
solver
relative_tolerance (float): the relative tolerance of the newton
solver
maximum_iterations (int, optional): maximum iterations allowed for
the solver to converge. Defaults to 30.
transient (bool, optional): If set to True, the simulation will be
transient. Defaults to True.
final_time (float, optional): final time of the simulation.
Defaults to None.
chemical_pot (bool, optional): if True, conservation of chemical
potential will be assumed. Defaults to False.
soret (bool, optional): if True, Soret effect will be assumed.
Defaults to False.
traps_element_type (str, optional): Finite element used for traps.
If traps densities are discontinuous (eg. different materials)
"DG" is recommended. Defaults to "CG".
update_jacobian (bool, optional): If set to False, the Jacobian of
the formulation will be computed only once at the beggining.
Else it will be computed at each time step. Defaults to True.
completion_tone (bool, optional): If True, a native os alert
tone will alert user upon completion of current run. Defaults
to False.
"""
Everything is documented
Stepsize
my_sim.dt = my_stepsize
Stepsize
my_stepsize = F.Stepsize(
initial_value=1.2,
stepsize_change_change_ratio=1.2,
dt_min=1e-8
)
my_sim.dt = my_stepsize
Options to stop the adaptive stepsize
Stepsize
my_stepsize = F.Stepsize(
initial_value=1.2,
stepsize_change_change_ratio=1.2,
dt_min=1e-8,
t_stop=100,
stepsize_stop_max=2
)
my_sim.dt = my_stepsize
Options to stop the adaptive stepsize
ReadTheDocs
The best way to document code.
Requires FESTIM to be open-source 😀
Embed graphs in Slides
Embed webapps in Slides
Embed webapps in Slides
FESTIM 0.8
By Remi Delaporte-Mathurin
FESTIM 0.8
- 587