Activity Strategies¶

Particula Index / Particula / Particles / Activity Strategies

Auto-generated documentation for particula.particles.activity_strategies module.

ActivityIdealMass¶

Show source in activity_strategies.py:145

Calculate ideal activity based on mass fractions (Raoult's Law).

Attributes¶

None

Methods¶

activity : Computes activity from mass concentration, treating mass fractions as ideal.

Examples¶

Example Usage

import particula as par
strategy = par.particles.ActivityIdealMass()
a = strategy.activity([0.5, 1.0, 1.5])
# a -> ...

References¶

"Raoult's Law," Wikipedia.

Signature¶

class ActivityIdealMass(ActivityStrategy): ...

ActivityIdealMass().activity¶

Show source in activity_strategies.py:169

Calculate the activity of a species based on mass concentration.

Arguments¶

mass_concentration : Concentration of the species in kg/m^3.

Returns¶

Activity of the species, unitless.

Signature¶

def activity(
    self, mass_concentration: Union[float, NDArray[np.float64]]
) -> Union[float, NDArray[np.float64]]: ...

ActivityIdealMolar¶

Show source in activity_strategies.py:94

Calculate ideal activity based on mole fractions (Raoult's Law).

Attributes¶

molar_mass : Molar mass of the species in kg/mol.

Methods¶

activity : Computes ideal activity from mass concentration and molar mass.

Examples¶

Example Usage

import particula as par
strategy = par.particles.ActivityIdealMolar(molar_mass=0.018)
# mass_concentration in kg/m^3
a = strategy.activity(np.array([1.2, 2.5, 3.0]))
# a -> ...

References¶

"Raoult's Law," Wikipedia.

Signature¶

class ActivityIdealMolar(ActivityStrategy):
    def __init__(self, molar_mass: Union[float, NDArray[np.float64]] = 0.0): ...

ActivityIdealMolar().activity¶

Show source in activity_strategies.py:128

Calculate the activity of a species based on mass concentration.

Arguments¶

mass_concentration : Concentration of the species in kg/m^3.

Returns¶

Activity of the species, unitless.

Signature¶

def activity(
    self, mass_concentration: Union[float, NDArray[np.float64]]
) -> Union[float, NDArray[np.float64]]: ...

ActivityIdealVolume¶

Show source in activity_strategies.py:184

Calculate ideal activity based on volume fractions (Raoult's Law).

Attributes¶

density : The density of the species in kg/m^3, used to derive volume fractions from mass concentrations.

Methods¶

activity : Computes activity from mass concentration and density.

Examples¶

Example Usage

strategy = ActivityIdealVolume(density=1000.0)
a = strategy.activity(2.5)
# a -> ...

References¶

"Raoult's Law," Wikipedia.

Signature¶

class ActivityIdealVolume(ActivityStrategy):
    def __init__(self, density: Union[float, NDArray[np.float64]] = 0.0): ...

ActivityIdealVolume().activity¶

Show source in activity_strategies.py:216

Calculate the activity of a species based on mass concentration.

Arguments¶

mass_concentration : Concentration of the species in kg/m^3.
density : Density of the species in kg/m^3.

Returns¶

Activity of the species, unitless.

Signature¶

def activity(
    self, mass_concentration: Union[float, NDArray[np.float64]]
) -> Union[float, NDArray[np.float64]]: ...

ActivityKappaParameter¶

Show source in activity_strategies.py:235

Non-ideal activity strategy using the kappa hygroscopic parameter.

Attributes¶

kappa : Kappa hygroscopic parameters (array or scalar).
density : Densities (array or scalar) in kg/m^3.
molar_mass : Molar masses (array or scalar) in kg/mol.
water_index : Index identifying the water species in arrays.

Methods¶

activity : Computes non-ideal activity using kappa hygroscopicity approach.

Examples¶

Example Usage

import particula as par
import numpy as np
strategy = par.particles.ActivityKappaParameter(
    kappa=np.array([0.1, 0.0]),
    density=np.array([1000.0, 1200.0]),
    molar_mass=np.array([0.018, 0.058]),
    water_index=0,
)
a = strategy.activity(np.array([1.0, 2.0]))
# a -> ...

References¶

Petters, M. D., & Kreidenweis, S. M. (2007). A single parameter representation of hygroscopic growth and cloud condensation nucleus activity. Atmospheric Chemistry and Physics, 7(8), 1961-1971. DOI.

Signature¶

class ActivityKappaParameter(ActivityStrategy):
    def __init__(
        self,
        kappa: NDArray[np.float64] = np.array([0.0], dtype=np.float64),
        density: NDArray[np.float64] = np.array([0.0], dtype=np.float64),
        molar_mass: NDArray[np.float64] = np.array([0.0], dtype=np.float64),
        water_index: int = 0,
    ): ...

ActivityKappaParameter().activity¶

Show source in activity_strategies.py:291

Calculate the activity of a species based on mass concentration.

Arguments¶

mass_concentration : Concentration of the species in kg/m^3.

Returns¶

Activity of the species, unitless.

References¶

Petters, M. D., & Kreidenweis, S. M. (2007). A single parameter representation of hygroscopic growth and cloud condensation nucleus activity. Atmospheric Chemistry and Physics, 7(8), 1961-1971. DOI.

Signature¶

def activity(
    self, mass_concentration: Union[float, NDArray[np.float64]]
) -> Union[float, NDArray[np.float64]]: ...

ActivityStrategy¶

Show source in activity_strategies.py:22

Abstract base class for vapor pressure and activity calculations.

This interface is used by subclasses for computing particle activity and partial pressures. General methods include activity() and partial_pressure().

Attributes¶

None

Methods¶

get_name : Return the type of the activity strategy.
activity : Calculate the activity of a species. (abstract method)
partial_pressure : Calculate the partial pressure of a species using its pure vapor pressure and computed activity.

Examples¶

Example Subclass

class CustomActivity(ActivityStrategy):
    def activity(self, mass_concentration):
        return 1.0

my_activity = CustomActivity()
pvap = my_activity.partial_pressure(101325.0, 1.0)
# pvap -> 101325.0

References¶

"Vapor Pressure," Wikipedia.

Signature¶

class ActivityStrategy(ABC): ...

ActivityStrategy().activity¶

Show source in activity_strategies.py:55

Calculate the activity of a species based on its mass concentration.

Arguments¶

mass_concentration : Concentration of the species in kg/m^3.

Returns¶

Activity of the species, unitless.

Signature¶

@abstractmethod
def activity(
    self, mass_concentration: Union[float, NDArray[np.float64]]
) -> Union[float, NDArray[np.float64]]: ...

ActivityStrategy().get_name¶

Show source in activity_strategies.py:69

Return the type of the activity strategy.

Signature¶

def get_name(self) -> str: ...

ActivityStrategy().partial_pressure¶

Show source in activity_strategies.py:73

Calculate the vapor pressure of species in the particle phase.

Arguments¶

pure_vapor_pressure : Pure vapor pressure of the species in Pa.
mass_concentration : Concentration of the species in kg/m^3.

Returns¶

Vapor pressure of the particle in Pa.

Signature¶

def partial_pressure(
    self,
    pure_vapor_pressure: Union[float, NDArray[np.float64]],
    mass_concentration: Union[float, NDArray[np.float64]],
) -> Union[float, NDArray[np.float64]]: ...

Activity Strategies¶

ActivityIdealMass¶

Attributes¶

Methods¶

Examples¶

References¶

Signature¶

See also¶

ActivityIdealMass().activity¶

Arguments¶

Returns¶

Signature¶

ActivityIdealMolar¶

Attributes¶

Methods¶

Examples¶

References¶

Signature¶

See also¶

ActivityIdealMolar().activity¶

Arguments¶

Returns¶

Signature¶

ActivityIdealVolume¶

Attributes¶

Methods¶

Examples¶

References¶

Signature¶

See also¶

ActivityIdealVolume().activity¶

Arguments¶

Returns¶

Signature¶

ActivityKappaParameter¶

Attributes¶

Methods¶

Examples¶

References¶

Signature¶

See also¶

ActivityKappaParameter().activity¶

Arguments¶

Returns¶

References¶

Signature¶

ActivityStrategy¶

Attributes¶

Methods¶

Examples¶

References¶

Signature¶

ActivityStrategy().activity¶

Arguments¶

Returns¶

Signature¶

ActivityStrategy().get_name¶

Signature¶

ActivityStrategy().partial_pressure¶

Arguments¶

Returns¶

Signature¶