"""Ideal gas Module."""
from typing import List, Union
import numpy as np
from numpy.typing import NDArray
from reactord.substance import Substance
from scipy.constants import R
from .abstract_mix import AbstractMix
[docs]class IdealGas(AbstractMix):
"""IdealGas object class.
This class should be used when the mixture is considered an ideal gas.
Parameters
----------
substance_list : list[Substance]
list of substance objects
viscosity_mixing_rule : str, optional
Viscosity mixing rule method. Options available: "linear",
"grunberg_nissan", "herning_zipperer"., by default "herning_zipperer"
Attributes
----------
phase_nature : str
gas.
substances : List [Substance]
List of substances.
viscosity_mixing_rule : str
Viscosity mixing rule method.
"""
def __init__(
self,
substance_list: List[Substance],
viscosity_mixing_rule: str = "herning_zipperer",
) -> None:
super().__init__(
substance_list=substance_list,
phase_nature="gas",
viscosity_mixing_rule=viscosity_mixing_rule,
)
[docs] def volume(
self,
mole_fractions: np.ndarray,
temperature: Union[float, NDArray[np.float64]],
pressure: Union[float, NDArray[np.float64]],
) -> float:
r"""Return the molar volume of the mixture.
Multiple mixture compositions can be specified by a moles matrix. Each
column of the matrix represents each mixture and each row represents
each substance's mole fractions. Also with temperature and pressure
vectors following de NumPy broadcasting rules.
.. math::
v = \frac {R T} {P}
| :math:`v`: mix's molar volume.
| :math:`R`: Ideal gas constant = 8.31446261815324
:math:`\frac {m^3 Pa} {K mol}`
| :math:`T`: temperature.
| :math:`P`: pressure.
Parameters
----------
mole_fractions : NDArray[np.float64]
mole fractions of each substance specified in the same order as the
mix's substances order.
temperature: Union[float, NDArray[np.float64]]
Temperature. [K]
pressure: Union[float, NDArray[np.float64]]
Pressure. [Pa]
Returns
-------
Union[float, NDArray[np.float64]]
Mixture's molar volume. [m³/mol]
"""
volume = R * np.divide(temperature, pressure)
return volume
[docs] def mix_heat_capacity(
self,
mole_fractions: np.ndarray,
temperature: Union[float, NDArray[np.float64]],
pressure: Union[float, NDArray[np.float64]],
) -> float:
r"""Calculate the mixture's heat capacity [J/mol].
Multiple mixture compositions can be specified by a moles matrix. Each
column of the matrix represents each mixture and each row represents
each substance's mole fractions. Also with temperature and pressure
vectors following de NumPy broadcasting rules.
.. math::
C_{p_{mix}} = \sum_{i=0}^{N} z_i C_{p_i}
| :math:`C_{p_{mix}}`: mix's heat capacity.
| :math:`N`: total number of substances in the mixture.
| :math:`C_{p_i}`: ideal gas heat capacity of the mix's
:math:`i`-th substance.
| :math:`z_i`: mole fraction of the mix's :math:`i`-th substance.
Parameters
----------
mole_fractions : np.ndarray [float]
mole fractions of each substance specified in the same order as the
mix's substances order.
temperature: Union[float, NDArray[np.float64]]
Temperature. [K]
pressure: Union[float, NDArray[np.float64]]
Pressure. [Pa]
Returns
-------
Union[float, NDArray[np.float64]]
Mixture's heat capacity. [J/mol]
Requires
--------
heat_capacity_gas defined on each mix's Substance.
"""
pure_cp = np.array(
[
substance.heat_capacity_gas(temperature, pressure)
for substance in self.substances
]
)
# The next line is equal to a column-wise dot product of the two arrays
mix_cp = np.multiply(mole_fractions, pure_cp).sum(axis=0)
return mix_cp