rizer.misc.ct_utils#

Classes#

CanteraStringInputThermo

CanteraStringInput

Functions#

load_goutier2025_mechanism(→ cantera.Solution)

Load the Goutier2025 mechanism for CH4 to C2H2.

load_goutier2025_mechanism_with_options(→ cantera.Solution)

Load the Goutier2025 mechanism for CH4 to C2H2, with individually selectable options.

plot_chemical_equilibrium(thermo, initial_solution, ...)

Plot main species under thermochemical equilibrium with [Cantera].

get_similar_reactions(→ dict[int, cantera.Reaction])

Get all reactions in a cantera.Solution that are similar to reaction.

to_cantera_format(→ str)

Convert a reaction rate constant to Cantera format.

return_x_y_from_hydrocarbon(→ tuple[int, int])

Return the number of carbon atoms and hydrogen atoms in a hydrocarbon.

from_ct_dict_to_ct_str(→ str)

Convert a Cantera dictionary to a Cantera string.

Module Contents#

rizer.misc.ct_utils.load_goutier2025_mechanism(phase_name: str) → cantera.Solution#

Load the Goutier2025 mechanism for CH4 to C2H2.

The mechanism is loaded from the data/mechanisms/Goutier2025/CH4_to_C2H2.yaml file.

To properly load the mechanism, the following classes need to be imported from rizer.kin.extensible_rate:

  • ExtensibleElectronTemperaturePlasmaRateData

  • ExtensibleTwoTempPlasmaRateData

  • JanevDissociativeRecombinationC2Hy

  • DruyvesteynRate

  • ReverseTwoTemperaturePlasma

Even though the classes are imported, they are not used in this function. They are only used to ensure that the YAML file can be loaded by Cantera.

Parameters:

phase_name (str) –

Name of the phase to load. Could be:

  • plasma: Plasma phase without electronic excited states.

  • gas: Gas phase without electronic excited states.

  • plasma_with_electronic_excited_states: Plasma phase with electronic excited states.

  • gas_with_electronic_excited_states: Gas phase with electronic excited states.

  • plasma_druyvesteyn_with_electronic_excited_states: Plasma phase with electronic excited states and Druyvesteyn electron energy distribution function.

  • gas_druyvesteyn_with_electronic_excited_states: Gas phase with electronic excited states and Druyvesteyn electron energy distribution function.

Returns:

The loaded mechanism.

Return type:

cantera.Solution

rizer.misc.ct_utils.load_goutier2025_mechanism_with_options(thermo: str = 'plasma', electron_energy_distribution: str = 'maxwellian', electronic_excited_states: str | list[str] | None = 'None', radiative_ionization_included: bool = False) → cantera.Solution#

Load the Goutier2025 mechanism for CH4 to C2H2, with individually selectable options.

Unlike load_goutier2025_mechanism(), which loads one of a fixed set of pre-composed phases, this function dynamically assembles the phase from the same data/mechanisms/Goutier2025/CH4_to_C2H2.yaml file: it loads the phase that is the superset of species and reactions for the requested thermo and electron_energy_distribution, then filters species and reactions down to the requested electronic_excited_states and radiative_ionization_included. The YAML file itself is never modified.

Parameters:

  • thermo (str, optional) – Either plasma or gas, by default plasma.

  • electron_energy_distribution (str, optional) – Either maxwellian or Druyvesteyn, by default maxwellian.

  • electronic_excited_states (str, list of str, or None, optional) –

    Which atomic species to include electronically excited states for, by default None.

    • None or “None”: no electronically excited states.

    • atomic_C: electronically excited states of atomic carbon only.

    • atomic_H: electronically excited states of atomic hydrogen only.

    • [“atomic_C”, “atomic_H”]: electronically excited states of both.

    • all: equivalent to [“atomic_C”, “atomic_H”].

  • radiative_ionization_included (bool, optional) – The mechanism includes three radiative-recombination reactions (e- + C+ => C, e- + H+ => H, e- + H2+ => H + H), whose forward rate is physically correct. Their detailed-balance reverse reactions would represent radiative ionization (e.g. H + hnu => e- + H+), but a rate derived from detailed balance with the electron temperature does not correctly capture this photon-driven process. By default (False), these three reverse reactions are removed. If True, they are kept.

Returns:

The loaded mechanism.

Return type:

cantera.Solution

See also

load_goutier2025_mechanism

rizer.misc.ct_utils.plot_chemical_equilibrium(thermo: str | pathlib.Path, initial_solution: str | dict[str, float], temperatures: numpy.ndarray, unit: str = 'K', keep_only_first_species: int = 5, save_file_name: str | pathlib.Path | None = None, fraction: str = 'mole')#

Plot main species under thermochemical equilibrium with [Cantera].

Parameters:

  • thermo (str or pathlib.Path) – Cantera thermo file.

  • initial_solution (str or dict) – Initial solution (in mole). Either a string like “CH4:1, O2:2” or a dictionary like {“CH4”: 1, “O2”: 2}.

  • temperatures (numpy.ndarray) – Temperatures to evaluate.

  • unit (str, optional) – Temperature unit (“K” or “C”), by default “K”

  • keep_only_first_species (int, optional) – Keep only the first majority species, by default 5

  • save_file_name (str or pathlib.Path or None, optional) – Save file name, by default None

  • fraction (str, optional) – Display the result with “mole” or “mass” fraction, by default “mole”

rizer.misc.ct_utils.get_similar_reactions(reaction: str | cantera.Reaction, gas: cantera.Solution, verbose: bool = False) → dict[int, cantera.Reaction]#

Get all reactions in a cantera.Solution that are similar to reaction.

Similarity is defined as:

  • all the reactants of reaction are a subset of the reactants of one reaction in gas.

  • all the products of reaction are a subset of the reactants of one reaction in gas (happens when the reaction is reversible)

This function is used to give a hint on mistyped reactions.

Parameters:
Returns:

Dictionary of similar reactions.

  • Keys are the reaction index in gas.reactions().

  • Values are the corresponding reactions, as cantera.Reaction objects.

Return type:

dict of int to cantera.Reaction

Example

>>> import cantera as ct
>>> from rizer.misc.ct_utils import get_similar_reactions
>>> gas = ct.Solution("gri30.yaml")
>>> _ = get_similar_reactions("H + CH4 <=> CH3 + H2", gas, verbose=True)
Reactions similar to CH4 + H <=> CH3 + H2, with {'CH4': 1.0, 'H': 1.0} as either reactants or products, are {52: CH4 + H <=> CH3 + H2    <Arrhenius>}
rizer.misc.ct_utils.to_cantera_format(A: float, b: float, Ea: float, plasma: bool, equation: str, note: str, commented: bool = False, source: None | str = None, nist_url: None | str = None, umist_url: None | str = None, temperature_range: None | tuple[float, float] = None, see_also: None | str = None) → str#

Convert a reaction rate constant to Cantera format.

Parameters:

  • A (float) – Pre-exponential factor.

  • b (float) – Temperature exponent [-].

  • Ea (float) – Activation energy [K].

  • plasma (bool) – If True, the reaction is a plasma reaction.

  • equation (str) – Reaction equation.

  • note (str) – Note to add to the reaction.

  • commented (bool, optional) – If True, the reaction is commented, by default False.

  • source (None or str, optional) – Source of the reaction, by default None.

  • umist_url (None or str, optional) – URL to the [UMIST] database, by default None.

  • temperature_range (None or tuple of float, optional) – Temperature range validity of the reaction, by default None.

  • see_also (None or str, optional) – URL to a related reaction, by default None.

Returns:

Reaction rate constant in Cantera format.

Return type:

str

rizer.misc.ct_utils.return_x_y_from_hydrocarbon(hydrocarbon: str) → tuple[int, int]#

Return the number of carbon atoms and hydrogen atoms in a hydrocarbon.

Parameters:

hydrocarbon (str) – The name of the hydrocarbon, like CH4 or C2H6.

Returns:

The number of carbon atoms and hydrogen atoms in the hydrocarbon.

Return type:

tuple of int, int

Examples

>>> return_x_y_from_hydrocarbon("CH4")
(1, 4)
>>> return_x_y_from_hydrocarbon("C2H6")
(2, 6)
>>> return_x_y_from_hydrocarbon("C3H8")
(3, 8)
>>> return_x_y_from_hydrocarbon("C2")
(2, 0)
>>> return_x_y_from_hydrocarbon("C")
(1, 0)
>>> return_x_y_from_hydrocarbon("C2H")
(2, 1)
>>> return_x_y_from_hydrocarbon("C2H2")
(2, 2)
>>> return_x_y_from_hydrocarbon("H2")
(0, 2)
>>> import pytest
>>> with pytest.raises(ValueError):
...     return_x_y_from_hydrocarbon("N2")
...
>>> with pytest.raises(ValueError):
...     return_x_y_from_hydrocarbon("C2H2^+")
...
class rizer.misc.ct_utils.CanteraStringInputThermo#
model: str#
temperature_ranges: list[float]#
data: list[list[float]]#
class rizer.misc.ct_utils.CanteraStringInput#
name: str#
composition: str#
thermo: CanteraStringInputThermo#
notes: str#
rizer.misc.ct_utils.from_ct_dict_to_ct_str(ct_dict: CanteraStringInput) → str#

Convert a Cantera dictionary to a Cantera string.

Parameters:

ct_dict (CanteraStringInput) – A dictionary containing the NASA9 coefficients, compatible with Cantera’s YAML format.

Returns:

A string in Cantera format, that can be used in a YAML file.

Return type:

str