"""Material classes for the simulation framework."""
from typing import Literal, Optional, Union
import pydantic as pd
from numpy import sqrt
import flow360.component.simulation.units as u
from flow360.component.simulation.framework.base_model import Flow360BaseModel
from flow360.component.simulation.unit_system import (
AbsoluteTemperatureType,
DensityType,
PressureType,
SpecificHeatCapacityType,
ThermalConductivityType,
VelocityType,
ViscosityType,
)
class MaterialBase(Flow360BaseModel):
"""
Basic properties required to define a material.
For example: young's modulus, viscosity as an expression of temperature, etc.
"""
type: str = pd.Field()
name: str = pd.Field()
[docs]
class Sutherland(Flow360BaseModel):
"""
Represents Sutherland's law for calculating dynamic viscosity.
This class implements Sutherland's formula to compute the dynamic viscosity of a gas
as a function of temperature.
Example
-------
>>> fl.Sutherland(
... reference_viscosity=1.70138e-5 * fl.u.Pa * fl.u.s,
... reference_temperature=300.0 * fl.u.K,
... effective_temperature=110.4 * fl.u.K,
... )
====
"""
# pylint: disable=no-member
reference_viscosity: ViscosityType.NonNegative = pd.Field(
description="The reference dynamic viscosity at the reference temperature."
)
reference_temperature: AbsoluteTemperatureType = pd.Field(
description="The reference temperature associated with the reference viscosity."
)
effective_temperature: AbsoluteTemperatureType = pd.Field(
description="The effective temperature constant used in Sutherland's formula."
)
[docs]
@pd.validate_call
def get_dynamic_viscosity(
self, temperature: AbsoluteTemperatureType
) -> ViscosityType.NonNegative:
"""
Calculates the dynamic viscosity at a given temperature using Sutherland's law.
Parameters
----------
temperature : AbsoluteTemperatureType
The temperature at which to calculate the dynamic viscosity.
Returns
-------
ViscosityType.NonNegative
The calculated dynamic viscosity at the specified temperature.
"""
return self.reference_viscosity * float(
pow(temperature / self.reference_temperature, 1.5)
* (self.reference_temperature + self.effective_temperature)
/ (temperature + self.effective_temperature)
)
# pylint: disable=no-member, missing-function-docstring
[docs]
class Air(MaterialBase):
"""
Represents the material properties for air.
This sets specific material properties for air,
including dynamic viscosity, specific heat ratio, gas constant, and Prandtl number.
Example
-------
>>> fl.Air(
... dynamic_viscosity=1.063e-05 * fl.u.Pa * fl.u.s
... )
====
"""
type: Literal["air"] = pd.Field("air", frozen=True)
name: str = pd.Field("air")
dynamic_viscosity: Union[Sutherland, ViscosityType.NonNegative] = pd.Field(
Sutherland(
reference_viscosity=1.716e-5 * u.Pa * u.s,
reference_temperature=273.15 * u.K,
# pylint: disable=fixme
# TODO: validation error for effective_temperature not equal 110.4 K
effective_temperature=110.4 * u.K,
),
description=(
"The dynamic viscosity model or value for air. Defaults to a `Sutherland` "
"model with standard atmospheric conditions."
),
)
@property
def specific_heat_ratio(self) -> pd.PositiveFloat:
"""
Returns the specific heat ratio (gamma) for air.
Returns
-------
pd.PositiveFloat
The specific heat ratio, typically 1.4 for air.
"""
return 1.4
@property
def gas_constant(self) -> SpecificHeatCapacityType.Positive:
"""
Returns the specific gas constant for air.
Returns
-------
SpecificHeatCapacityType.Positive
The specific gas constant for air.
"""
return 287.0529 * u.m**2 / u.s**2 / u.K
@property
def prandtl_number(self) -> pd.PositiveFloat:
"""
Returns the Prandtl number for air.
Returns
-------
pd.PositiveFloat
The Prandtl number, typically around 0.72 for air.
"""
return 0.72
[docs]
@pd.validate_call
def get_pressure(
self, density: DensityType.Positive, temperature: AbsoluteTemperatureType
) -> PressureType.Positive:
"""
Calculates the pressure of air using the ideal gas law.
Parameters
----------
density : DensityType.Positive
The density of the air.
temperature : AbsoluteTemperatureType
The temperature of the air.
Returns
-------
PressureType.Positive
The calculated pressure.
"""
temperature = temperature.to("K")
return density * self.gas_constant * temperature
[docs]
@pd.validate_call
def get_speed_of_sound(self, temperature: AbsoluteTemperatureType) -> VelocityType.Positive:
"""
Calculates the speed of sound in air at a given temperature.
Parameters
----------
temperature : AbsoluteTemperatureType
The temperature at which to calculate the speed of sound.
Returns
-------
VelocityType.Positive
The speed of sound at the specified temperature.
"""
temperature = temperature.to("K")
return sqrt(self.specific_heat_ratio * self.gas_constant * temperature)
[docs]
@pd.validate_call
def get_dynamic_viscosity(
self, temperature: AbsoluteTemperatureType
) -> ViscosityType.NonNegative:
"""
Calculates the dynamic viscosity of air at a given temperature.
Parameters
----------
temperature : AbsoluteTemperatureType
The temperature at which to calculate the dynamic viscosity.
Returns
-------
ViscosityType.NonNegative
The dynamic viscosity at the specified temperature.
"""
if temperature.units is u.degC or temperature.units is u.degF:
temperature = temperature.to("K")
if isinstance(self.dynamic_viscosity, Sutherland):
return self.dynamic_viscosity.get_dynamic_viscosity(temperature)
return self.dynamic_viscosity
[docs]
class SolidMaterial(MaterialBase):
"""
Represents the solid material properties for heat transfer volume.
Example
-------
>>> fl.SolidMaterial(
... name="aluminum",
... thermal_conductivity=235 * fl.u.kg / fl.u.s**3 * fl.u.m / fl.u.K,
... density=2710 * fl.u.kg / fl.u.m**3,
... specific_heat_capacity=903 * fl.u.m**2 / fl.u.s**2 / fl.u.K,
... )
====
"""
type: Literal["solid"] = pd.Field("solid", frozen=True)
name: str = pd.Field(frozen=True, description="Name of the solid material.")
thermal_conductivity: ThermalConductivityType.Positive = pd.Field(
frozen=True, description="Thermal conductivity of the material."
)
density: Optional[DensityType.Positive] = pd.Field(
None, frozen=True, description="Density of the material."
)
specific_heat_capacity: Optional[SpecificHeatCapacityType.Positive] = pd.Field(
None, frozen=True, description="Specific heat capacity of the material."
)
aluminum = SolidMaterial(
name="aluminum",
thermal_conductivity=235 * u.kg / u.s**3 * u.m / u.K,
density=2710 * u.kg / u.m**3,
specific_heat_capacity=903 * u.m**2 / u.s**2 / u.K,
)
[docs]
class Water(MaterialBase):
"""
Water material used for :class:`LiquidOperatingCondition`
Example
-------
>>> fl.Water(
... name="Water",
... density=1000 * fl.u.kg / fl.u.m**3,
... dynamic_viscosity=0.001002 * fl.u.kg / fl.u.m / fl.u.s,
... )
====
"""
type: Literal["water"] = pd.Field("water", frozen=True)
name: str = pd.Field(frozen=True, description="Custom name of the water with given property.")
density: Optional[DensityType.Positive] = pd.Field(
1000 * u.kg / u.m**3, frozen=True, description="Density of the water."
)
dynamic_viscosity: ViscosityType.NonNegative = pd.Field(
0.001002 * u.kg / u.m / u.s, frozen=True, description="Dynamic viscosity of the water."
)
SolidMaterialTypes = SolidMaterial
FluidMaterialTypes = Union[Air, Water]
