cantera/interfaces/python/ck2cti.py
2012-03-30 23:48:44 +00:00

1819 lines
73 KiB
Python
Executable file

#!/usr/bin/env python
# encoding: utf-8
################################################################################
#
# Copyright (c) 2009-2011 by the RMG Team (rmg_dev@mit.edu)
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the 'Software'),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
# DEALINGS IN THE SOFTWARE.
#
################################################################################
"""
This module contains functions for converting Chemkin input files to
Cantera input files (CTI).
"""
import logging
import re
import types
import numpy as np
################################################################################
UNIT_OPTIONS = {'CAL/': 'cal/mol',
'CAL/MOL': 'cal/mol',
'CAL/MOLE': 'cal/mol',
'EVOL': 'eV',
'EVOLTS': 'eV',
'JOUL': 'J/mol',
'JOULES/MOL': 'J/mol',
'JOULES/MOLE': 'J/mol',
'KCAL': 'kcal/mol',
'KCAL/MOL': 'kcal/mol',
'KCAL/MOLE': 'kcal/mol',
'KELV': 'K',
'KELVIN': 'K',
'KELVINS': 'K',
'KJOU': 'kJ/mol',
'KJOULES/MOL': 'kJ/mol',
'KJOULES/MOLE': 'kJ/mol',
'MOL': 'mol',
'MOLE': 'mol',
'MOLES': 'mol',
'MOLEC': 'molec',
'MOLECULES': 'molec'}
ENERGY_UNITS = 'cal/mol'
QUANTITY_UNITS = 'mol'
################################################################################
class ChemkinError(Exception):
"""
An exception class for exceptional behavior involving Chemkin files. Pass a
string describing the circumstances that caused the exceptional behavior.
"""
pass
################################################################################
class Species(object):
def __init__(self, label):
self.label = label
self.thermo = None
self.transport = None
self.note = None
self.composition = None
def __str__(self):
return self.label
def __repr__(self):
return 'Species({0!r})'.format(self.label)
def to_cti(self, indent=0):
lines = []
atoms = ' '.join('{0}:{1}'.format(*a) for a in self.composition.iteritems())
prefix = ' '*(indent+8)
lines.append('species(name={0!r},'.format(self.label))
lines.append(prefix + 'atoms={0!r},'.format(atoms))
if self.thermo:
lines.append(prefix + 'thermo={0},'.format(self.thermo.to_cti(15+indent)))
if self.transport:
lines.append(prefix + 'transport={0},'.format(self.transport.to_cti(14+indent)))
if self.note:
lines.append(prefix + 'note={0!r},'.format(self.note))
lines[-1] = lines[-1][:-1] + ')'
lines.append('')
return '\n'.join(lines)
################################################################################
class ThermoModel:
"""
A base class for thermodynamics models, containing several attributes
common to all models:
=============== =================== ========================================
Attribute Type Description
=============== =================== ========================================
`Tmin` ``float`` The minimum temperature at which the model is valid, or ``None`` if unknown or undefined
`Tmax` ``float`` The maximum temperature at which the model is valid, or ``None`` if unknown or undefined
`comment` ``str`` Information about the model (e.g. its source)
=============== =================== ========================================
"""
def __init__(self, Tmin=None, Tmax=None, comment=''):
if Tmin is not None:
self.Tmin = Tmin
else:
self.Tmin = None
if Tmax is not None:
self.Tmax = Tmax
else:
self.Tmax = None
self.comment = comment
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
ThermoModel object.
"""
return 'ThermoModel(Tmin={0!r}, Tmax={1!r}, comment="""{2}""")'.format(self.Tmin, self.Tmax, self.comment)
################################################################################
class NASA(ThermoModel):
"""
A single NASA polynomial for thermodynamic data. The `coeffs` attribute
stores the seven or nine polynomial coefficients
:math:`\\mathbf{a} = \\left[a_{-2}\\ a_{-1}\\ a_0\\ a_1\\ a_2\\ a_3\\ a_4\\ a_5\\ a_6 \\right]`
from which the relevant thermodynamic parameters are evaluated via the
expressions
.. math:: \\frac{C_\\mathrm{p}(T)}{R} = a_{-2} T^{-2} + a_{-1} T^{-1} + a_0 + a_1 T + a_2 T^2 + a_3 T^3 + a_4 T^4
.. math:: \\frac{H(T)}{RT} = - a_{-2} T^{-2} + a_{-1} T^{-1} \\ln T + a_0 + \\frac{1}{2} a_1 T + \\frac{1}{3} a_2 T^2 + \\frac{1}{4} a_3 T^3 + \\frac{1}{5} a_4 T^4 + \\frac{a_5}{T}
.. math:: \\frac{S(T)}{R} = -\\frac{1}{2} a_{-2} T^{-2} - a_{-1} T^{-1} + a_0 \\ln T + a_1 T + \\frac{1}{2} a_2 T^2 + \\frac{1}{3} a_3 T^3 + \\frac{1}{4} a_4 T^4 + a_6
The coefficients are stored internally in the nine-coefficient format, even
when only seven coefficients are provided.
"""
def __init__(self, coeffs, Tmin=None, Tmax=None, comment=''):
ThermoModel.__init__(self, Tmin=Tmin, Tmax=Tmax, comment=comment)
coeffs = coeffs or (0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0)
if len(coeffs) == 7:
self.cm2 = 0.0; self.cm1 = 0.0
self.c0, self.c1, self.c2, self.c3, self.c4, self.c5, self.c6 = coeffs
elif len(coeffs) == 9:
self.cm2, self.cm1, self.c0, self.c1, self.c2, self.c3, self.c4, self.c5, self.c6 = coeffs
else:
raise ChemkinError('Invalid number of NASA polynomial coefficients; should be 7 or 9.')
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
object.
"""
string = 'NASA(Tmin={0!r}, Tmax={1!r}'.format(self.Tmin, self.Tmax)
if self.cm2 == 0 and self.cm1 == 0:
string += ', coeffs=[{0:g},{1:g},{2:g},{3:g},{4:g},{5:g},{6:g}]'.format(self.c0, self.c1, self.c2, self.c3, self.c4, self.c5, self.c6)
else:
string += ', coeffs=[{0:g},{1:g},{2:g},{3:g},{4:g},{5:g},{6:g},{7:g},{8:g}]'.format(self.cm2, self.cm1, self.c0, self.c1, self.c2, self.c3, self.c4, self.c5, self.c6)
if self.comment != '': string += ', comment="""{0}"""'.format(self.comment)
string += ')'
return string
def to_cti(self, indent=0):
prefix = ' '*indent
vals = self.c0, self.c1, self.c2, self.c3, self.c4, self.c5, self.c6
vals = ['{0: 15.8E}'.format(i) for i in vals]
lines = ['NASA([{0:.2f}, {1:.2f}],'.format(self.Tmin[0], self.Tmax[0]),
prefix+' [{0}, {1}, {2},'.format(*vals[0:3]),
prefix+' {0}, {1}, {2},'.format(*vals[3:6]),
prefix+' {0}]),'.format(vals[6])]
return '\n'.join(lines)
################################################################################
class MultiNASA(ThermoModel):
"""
A set of thermodynamic parameters given by NASA polynomials. This class
stores a list of :class:`NASA` objects in the `polynomials`
attribute. When evaluating a thermodynamic quantity, a polynomial that
contains the desired temperature within its valid range will be used.
"""
def __init__(self, polynomials=None, Tmin=0.0, Tmax=0.0, comment=''):
ThermoModel.__init__(self, Tmin=Tmin, Tmax=Tmax, comment=comment)
self.polynomials = polynomials or []
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
MultiNASA object.
"""
string = 'MultiNASA(Tmin={0!r}, Tmax={1!r}'.format(self.Tmin, self.Tmax)
string += ', polynomials=[{0}]'.format(','.join(['%r' % poly for poly in self.polynomials]))
if self.comment != '': string += ', comment="""{0}"""'.format(self.comment)
string += ')'
return string
def to_cti(self, indent=0):
prefix = ' '*indent
lines = []
for i,p in enumerate(self.polynomials):
if i == 0:
lines.append('({0}'.format(p.to_cti(indent+1)))
elif i != len(self.polynomials)-1:
lines.append(prefix + ' {0}'.format(p.to_cti(indent+1)))
else:
lines.append(prefix + ' {0})'.format(p.to_cti(indent+1)[:-1]))
return '\n'.join(lines)
################################################################################
class Reaction(object):
"""
A chemical reaction. The attributes are:
=================== =========================== ============================
Attribute Type Description
=================== =========================== ============================
`index` :class:`int` A unique nonnegative integer index
`reactants` :class:`list` The reactant species (as :class:`Species` objects)
`products` :class:`list` The product species (as :class:`Species` objects)
`kinetics` :class:`KineticsModel` The kinetics model to use for the reaction
`reversible` ``bool`` ``True`` if the reaction is reversible, ``False`` if not
`transitionState` :class:`TransitionState` The transition state
`thirdBody` ``bool`` ``True`` if the reaction if the reaction kinetics imply a third body, ``False`` if not
`duplicate` ``bool`` ``True`` if the reaction is known to be a duplicate, ``False`` if not
`degeneracy` :class:`double` The reaction path degeneracy for the reaction
`pairs` ``list`` Reactant-product pairings to use in converting reaction flux to species flux
=================== =========================== ============================
"""
def __init__(self, index=-1, reactants=None, products=None,
kinetics=None, reversible=True, transitionState=None,
thirdBody=False, duplicate=False, degeneracy=1, pairs=None):
self.index = index
self.reactants = reactants
self.products = products
self.kinetics = kinetics
self.reversible = reversible
self.transitionState = transitionState
self.thirdBody = thirdBody
self.duplicate = duplicate
self.degeneracy = degeneracy
self.pairs = pairs
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
object.
"""
string = 'Reaction('
if self.index != -1:
string += 'index={0:d}, '.format(self.index)
if self.reactants is not None:
string += 'reactants={0!r}, '.format(self.reactants)
if self.products is not None:
string += 'products={0!r}, '.format(self.products)
if self.kinetics is not None:
string += 'kinetics={0!r}, '.format(self.kinetics)
if not self.reversible:
string += 'reversible={0}, '.format(self.reversible)
if self.transitionState is not None:
string += 'transitionState={0!r}, '.format(self.transitionState)
if self.thirdBody:
string += 'thirdBody={0}, '.format(self.thirdBody)
if self.duplicate:
string += 'duplicate={0}, '.format(self.duplicate)
if self.degeneracy != 1:
string += 'degeneracy={0:d}, '.format(self.degeneracy)
if self.pairs is not None:
string += 'pairs={0}, '.format(self.pairs)
string = string[:-2] + ')'
return string
def __str__(self):
"""
Return a string representation of the reaction, in the form 'A + B <=> C + D'.
"""
arrow = ' <=> '
if not self.reversible: arrow = ' -> '
return arrow.join([' + '.join([str(s) for s in self.reactants]), ' + '.join([str(s) for s in self.products])])
def hasTemplate(self, reactants, products):
"""
Return ``True`` if the reaction matches the template of `reactants`
and `products`, which are both lists of :class:`Species` objects, or
``False`` if not.
"""
return ((all([spec in self.reactants for spec in reactants]) and
all([spec in self.products for spec in products])) or
(all([spec in self.products for spec in reactants]) and
all([spec in self.reactants for spec in products])))
def to_cti(self, indent=0):
arrow = ' <=> ' if self.reversible else ' => '
reactantstr = ' + '.join(str(s) for s in self.reactants)
productstr= ' + '.join(str(s) for s in self.products)
kinstr = self.kinetics.to_cti(reactantstr, arrow, productstr, indent)
if self.duplicate:
k_indent = ' ' * (kinstr.find('(') + 1)
kinstr = kinstr[:-1] + ",\n{0}options='duplicate')".format(k_indent)
return kinstr
if self.thirdBody:
reactantstr += ' + M'
productstr += ' + M'
ctiReactionClass = 'three_body_reaction'
elif isinstance(self.kinetics, (Lindemann, Troe, Chebyshev)):
reactantstr += ' (+ M)'
productstr += ' (+ M)'
ctiReactionClass = 'falloff_reaction'
else:
ctiReactionClass = 'reaction'
prefix = ' '*(indent+len(self.rxnClass+1))
reactionstr = reactantstr + arrow + productstr
if isinstance(self.kinetics, (Arrhenius, ThirdBody)):
Arates = ' [{0.A}, {0.n}, {0.Ea}]'.format(self.kinetics)
else:
Arates = ''
lines = ['{0}({1!r}{2},'.format(ctiReactionClass, reactionstr, Arates)]
if self.thirdBody:
lines.append(prefix + 'efficiencies=')
lines[-1] = lines[-1][:-1] + ')'
return '\n'.join(lines)
################################################################################
class KineticsModel(object):
"""
A base class for kinetics models, containing several attributes common to
all models:
=============== =================== ========================================
Attribute Type Description
=============== =================== ========================================
`Tmin` :class:`Quantity` The minimum absolute temperature in K at which the model is valid
`Tmax` :class:`Quantity` The maximum absolute temperature in K at which the model is valid
`Pmin` :class:`Quantity` The minimum absolute pressure in Pa at which the model is valid
`Pmax` :class:`Quantity` The maximum absolute pressure in Pa at which the model is valid
`comment` :class:`str` A string containing information about the model (e.g. its source)
=============== =================== ========================================
"""
def __init__(self, Tmin=None, Tmax=None, Pmin=None, Pmax=None, comment=''):
if Tmin is not None:
self.Tmin = Tmin
else:
self.Tmin = None
if Tmax is not None:
self.Tmax = Tmax
else:
self.Tmax = None
if Pmin is not None:
self.Pmin = Pmin
else:
self.Pmin = None
if Pmax is not None:
self.Pmax = Pmax
else:
self.Pmax = None
self.comment = comment
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
KineticsModel object.
"""
string = self.toPrettyRepr()
string = re.sub(r'\(\n ', '(', string)
string = re.sub(r',\n ', ', ', string)
string = re.sub(r',\n\)', ')', string)
string = re.sub(r' = ', '=', string)
return string
def toPrettyRepr(self):
"""
Return a string representation that can be used to reconstruct the
KineticsModel object.
"""
raise NotImplementedError('You must implement this method in your derived class.')
def __reduce__(self):
"""
A helper function used when pickling a KineticsModel object.
"""
return (KineticsModel, (self.Tmin, self.Tmax, self.Pmin, self.Pmax, self.comment))
def isPressureDependent(self):
"""
Return ``True`` if the kinetics are pressure-dependent or ``False`` if
they are pressure-independent. This method must be overloaded in the
derived class.
"""
raise ChemkinError('Unexpected call to KineticsModel.isPressureDependent(); you should be using a class derived from KineticsModel.')
def to_cti(self, reactantstr, arrow, productstr):
raise ChemkinError('to_cti is not implemented for objects of class {0}'.format(self.__class__.__name__))
def efficiencyString(self):
if hasattr(self, 'efficiencies'):
return ' '.join('{0}:{1}'.format(mol, eff)
for mol,eff in self.efficiencies.iteritems())
else:
return ''
################################################################################
class KineticsData(KineticsModel):
"""
A kinetics model based around a set of discrete (high-pressure limit)
rate coefficients at various temperatures. The attributes are:
=========== =================== ============================================
Attribute Type Description
=========== =================== ============================================
`Tdata` :class:`Quantity` The temperatures at which the heat capacity data is provided
`kdata` :class:`Quantity` The rate coefficients in SI units at each temperature in `Tdata`
=========== =================== ============================================
"""
def __init__(self, Tdata=None, kdata=None, Tmin=None, Tmax=None, comment=''):
KineticsModel.__init__(self, Tmin=Tmin, Tmax=Tmax, comment=comment)
self.Tdata = Tdata
self.kdata = kdata
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'KineticsData(\n'
string += u' Tdata = {0!r},\n'.format(self.Tdata)
string += u' kdata = {0!r},\n'.format(self.kdata)
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __reduce__(self):
"""
A helper function used when pickling a KineticsData object.
"""
return (KineticsData, (self.Tdata, self.kdata, self.Tmin, self.Tmax, self.comment))
def isPressureDependent(self):
"""
Returns ``False`` since KineticsData kinetics are not
pressure-dependent.
"""
return False
################################################################################
class Arrhenius(KineticsModel):
"""
Represent a set of modified Arrhenius kinetics. The kinetic expression has
the form
.. math:: k(T) = A \\left( \\frac{T}{T_0} \\right)^n \\exp \\left( - \\frac{E_\\mathrm{a}}{RT} \\right)
where :math:`A`, :math:`n`, :math:`E_\\mathrm{a}`, and :math:`T_0` are the
parameters to be set, :math:`T` is absolute temperature, and :math:`R` is
the gas law constant. The attributes are:
=============== =================== ========================================
Attribute Type Description
=============== =================== ========================================
`A` :class:`Quantity` The preexponential factor in s^-1, m^3/mol*s, etc.
`T0` :class:`Quantity` The reference temperature in K
`n` :class:`Quantity` The temperature exponent
`Ea` :class:`Quantity` The activation energy in J/mol
=============== =================== ========================================
"""
def __init__(self, A=0.0, n=0.0, Ea=0.0, T0=1.0, Tmin=None, Tmax=None, comment=''):
KineticsModel.__init__(self, Tmin=Tmin, Tmax=Tmax, comment=comment)
self.A = A
self.T0 = T0
self.n = n
self.Ea = Ea
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'Arrhenius(\n'
string += u' A = {0!r},\n'.format(self.A)
string += u' n = {0!r},\n'.format(self.n)
string += u' Ea = {0!r},\n'.format(self.Ea)
string += u' T0 = {0!r},\n'.format(self.T0)
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __str__(self):
"""
Return a string representation that is a bit shorter and prettier than __repr__.
"""
string = 'Arrhenius(A={0!r}, n={1!r}, Ea={2!r}, T0={3!r})'.format(self.A, self.n, self.Ea, self.T0)
return string
def __reduce__(self):
"""
A helper function used when pickling an Arrhenius object.
"""
return (Arrhenius, (self.A, self.n, self.Ea, self.T0, self.Tmin, self.Tmax, self.comment))
def isPressureDependent(self):
"""
Returns ``False`` since Arrhenius kinetics are not pressure-dependent.
"""
return False
def rateStr(self):
return '[{0.A[0]:e}, {0.n}, {0.Ea[0]}]'.format(self)
def to_cti(self, reactantstr, arrow, productstr, indent=0):
rxnstring = reactantstr + arrow + productstr
return 'reaction({0!r}, {1})'.format(rxnstring, self.rateStr())
################################################################################
class PDepArrhenius(KineticsModel):
"""
A kinetic model of a phenomenological rate coefficient k(T, P) using the
expression
.. math:: k(T,P) = A(P) T^{n(P)} \\exp \\left[ \\frac{-E_\\mathrm{a}(P)}{RT} \\right]
where the modified Arrhenius parameters are stored at a variety of pressures
and interpolated between on a logarithmic scale. The attributes are:
=============== ================== ============================================
Attribute Type Description
=============== ================== ============================================
`pressures` :class:`list` The list of pressures in Pa
`arrhenius` :class:`list` The list of :class:`Arrhenius` objects at each pressure
`highPlimit` :class:`Arrhenius` The high (infinite) pressure limiting :class:`Arrhenius` expression
=============== ================== ============================================
Note that `highPlimit` is not used in evaluating k(T,P).
"""
def __init__(self, pressures=None, arrhenius=None, highPlimit=None, Tmin=None, Tmax=None, Pmin=None, Pmax=None, comment=''):
KineticsModel.__init__(self, Tmin=Tmin, Tmax=Tmax, Pmin=Pmin, Pmax=Pmax, comment=comment)
self.pressures = pressures
self.arrhenius = arrhenius or []
self.highPlimit = highPlimit or None
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'MultiKinetics(\n'
string += u' pressures = {0!r},\n'.format(self.pressures)
string += u' arrhenius = [\n'
for kinetics in self.arrhenius:
for line in kinetics.toPrettyRepr().splitlines():
string += u' {0}\n'.format(line)
string += u' ],\n'
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.Pmin is not None: string += ' Pmin = {0!r},\n'.format(self.Pmin)
if self.Pmax is not None: string += ' Pmax = {0!r},\n'.format(self.Pmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
PDepArrhenius object.
"""
string = 'PDepArrhenius(\n pressures={0!r},\n arrhenius=[\n {1}]'.format(self.pressures, ',\n '.join([repr(arrh) for arrh in self.arrhenius]))
if self.highPlimit is not None: string += ",\n highPlimit={0!r}".format(self.highPlimit)
if self.Tmin is not None: string += ', Tmin={0!r}'.format(self.Tmin)
if self.Tmax is not None: string += ', Tmax={0!r}'.format(self.Tmax)
if self.Pmin is not None: string += ', Pmin={0!r}'.format(self.Pmin)
if self.Pmax is not None: string += ', Pmax={0!r}'.format(self.Pmax)
if self.comment != '': string += ',\n comment="""{0}"""'.format(self.comment)
string += '\n)'
return string
def __reduce__(self):
"""
A helper function used when pickling a PDepArrhenius object.
"""
return (PDepArrhenius, (self.pressures, self.arrhenius, self.highPlimit, self.Tmin, self.Tmax, self.Pmin, self.Pmax, self.comment))
def isPressureDependent(self):
"""
Returns ``True`` since PDepArrhenius kinetics are pressure-dependent.
"""
return True
def to_cti(self, reactantstr, arrow, productstr, indent=0):
rxnstring = reactantstr + arrow + productstr
lines = ['pdep_arrhenius({0!r},'.format(rxnstring)]
prefix = ' '*(indent+15)
template = '[({0}, {1!r}), {2.A[0]:e}, {2.n}, {2.Ea[0]}],'
for pressure,arrhenius in zip(self.pressures[0], self.arrhenius):
lines.append(prefix + template.format(pressure,
self.pressures[1],
arrhenius))
lines[-1] = lines[-1][:-1] + ')'
return '\n'.join(lines)
################################################################################
class Chebyshev(KineticsModel):
"""
A kinetic model of a phenomenological rate coefficient k(T, P) using the
expression
.. math:: \\log k(T,P) = \\sum_{t=1}^{N_T} \\sum_{p=1}^{N_P} \\alpha_{tp} \\phi_t(\\tilde{T}) \\phi_p(\\tilde{P})
where :math:`\\alpha_{tp}` is a constant, :math:`\\phi_n(x)` is the
Chebyshev polynomial of degree :math:`n` evaluated at :math:`x`, and
.. math:: \\tilde{T} \\equiv \\frac{2T^{-1} - T_\\mathrm{min}^{-1} - T_\\mathrm{max}^{-1}}{T_\\mathrm{max}^{-1} - T_\\mathrm{min}^{-1}}
.. math:: \\tilde{P} \\equiv \\frac{2 \\log P - \\log P_\\mathrm{min} - \\log P_\\mathrm{max}}{\\log P_\\mathrm{max} - \\log P_\\mathrm{min}}
are reduced temperature and reduced pressures designed to map the ranges
:math:`(T_\\mathrm{min}, T_\\mathrm{max})` and
:math:`(P_\\mathrm{min}, P_\\mathrm{max})` to :math:`(-1, 1)`.
The attributes are:
=============== =============== ============================================
Attribute Type Description
=============== =============== ============================================
`coeffs` :class:`list` Matrix of Chebyshev coefficients
`kunits` ``str`` The units of the generated k(T, P) values
`degreeT` :class:`int` The number of terms in the inverse temperature direction
`degreeP` :class:`int` The number of terms in the log pressure direction
=============== =============== ============================================
"""
def __init__(self, coeffs=None, kunits='', Tmin=None, Tmax=None, Pmin=None, Pmax=None, comment=''):
KineticsModel.__init__(self, Tmin=Tmin, Tmax=Tmax, Pmin=Pmin, Pmax=Pmax, comment=comment)
if coeffs is not None:
self.coeffs = np.array(coeffs, np.float64)
self.degreeT = self.coeffs.shape[0]
self.degreeP = self.coeffs.shape[1]
else:
self.coeffs = None
self.degreeT = 0
self.degreeP = 0
self.kunits = kunits
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'Chebyshev(\n'
string += u' coeffs = [\n'
for i in range(self.degreeT):
string += u' [{0}]'.format(','.join(['{0:g}'.format(self.coeffs[i,j]) for j in range(self.degreeP)]))
string += u' ],\n'
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.Pmin is not None: string += ' Pmin = {0!r},\n'.format(self.Pmin)
if self.Pmax is not None: string += ' Pmax = {0!r},\n'.format(self.Pmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __repr__(self):
"""
Return a string representation that can be used to reconstruct the
Chebyshev object.
"""
coeffs = '['
for i in range(self.degreeT):
if i > 0: coeffs += ', '
coeffs += '[{0}]'.format(','.join(['{0:g}'.format(self.coeffs[i,j]) for j in range(self.degreeP)]))
coeffs += ']'
string = 'Chebyshev(coeffs={0}'.format(coeffs)
if self.kunits != '': string += ', kunits="{0}"'.format(self.kunits)
if self.Tmin is not None: string += ', Tmin={0!r}'.format(self.Tmin)
if self.Tmax is not None: string += ', Tmax={0!r}'.format(self.Tmax)
if self.Pmin is not None: string += ', Pmin={0!r}'.format(self.Pmin)
if self.Pmax is not None: string += ', Pmax={0!r}'.format(self.Pmax)
if self.comment != '': string += ', comment="""{0}"""'.format(self.comment)
string += ')'
return string
def __reduce__(self):
"""
A helper function used when pickling a Chebyshev object.
"""
return (Chebyshev, (self.coeffs, self.kunits, self.Tmin, self.Tmax, self.Pmin, self.Pmax, self.comment))
def isPressureDependent(self):
"""
Returns ``True`` since Chebyshev polynomial kinetics are
pressure-dependent.
"""
return True
def to_cti(self, reactantstr, arrow, productstr, indent=0):
rxnstr = reactantstr + ' (+ M)' + arrow + productstr + ' (+ M)'
prefix = ' '*(indent+19)
lines = ['chebyshev_reaction({0!r},'.format(rxnstr),
prefix + 'Tmin={0.Tmin}, Tmax={0.Tmax},'.format(self),
prefix + 'Pmin={0.Pmin}, Pmax={0.Pmax},'.format(self)]
for i in range(self.degreeT):
coeffline = ', '.join('{0: 12.5e}'.format(self.coeffs[i,j]) for j in range(self.degreeP))
if i == 0:
lines.append(prefix + 'coeffs=[[{0}],'.format(coeffline))
else:
lines.append(prefix + ' [{0}],'.format(coeffline))
lines[-1] = lines[-1][:-1] + '])'
return '\n'.join(lines)
################################################################################
class ThirdBody(KineticsModel):
"""
A kinetic model of a phenomenological rate coefficient k(T, P) using the
expression
.. math:: k(T,P) = k(T) [\\ce{M}]
where :math:`k(T)` is an Arrhenius expression and
:math:`[\\ce{M}] \\approx P/RT` is the concentration of the third body
(i.e. the bath gas). A collision efficiency can be used to further correct
the value of :math:`k(T,P)`.
The attributes are:
=============== ======================= ====================================
Attribute Type Description
=============== ======================= ====================================
`arrheniusHigh` :class:`Arrhenius` The Arrhenius kinetics
`efficiencies` ``dict`` A mapping of species to collider efficiencies
=============== ======================= ====================================
"""
def __init__(self, arrheniusHigh=None, efficiencies=None, Tmin=None, Tmax=None, Pmin=None, Pmax=None, comment=''):
KineticsModel.__init__(self, Tmin=Tmin, Tmax=Tmax, Pmin=Pmin, Pmax=Pmax, comment=comment)
self.arrheniusHigh = arrheniusHigh
self.efficiencies = {}
if efficiencies is not None:
for mol, eff in efficiencies.iteritems():
self.efficiencies[mol] = eff
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'ThirdBody(\n'
lines = self.arrheniusHigh.toPrettyRepr().splitlines()
string += u' arrheniusHigh = {0}\n'.format(lines[0])
for line in lines[1:-1]:
string += u' {0}\n'.format(line)
string += u' ),\n'
if len(self.efficiencies) > 0:
string += u' efficiencies = {\n'
for species in sorted(self.efficiencies):
string += u' "{0}": {1:g},\n'.format(species, self.efficiencies[species])
string += u' },\n'
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.Pmin is not None: string += ' Pmin = {0!r},\n'.format(self.Pmin)
if self.Pmax is not None: string += ' Pmax = {0!r},\n'.format(self.Pmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __reduce__(self):
"""
A helper function used when pickling a ThirdBody object.
"""
return (ThirdBody, (self.arrheniusHigh, self.efficiencies, self.Tmin, self.Tmax, self.Pmin, self.Pmax, self.comment))
def isPressureDependent(self):
"""
Returns ``True`` since third-body kinetics are pressure-dependent.
"""
return True
def getColliderEfficiency(self, collider):
"""
Return the collider efficiency for the specified `collider`, which can
take one of two forms:
* A single collider species. If the collider exists in the in the set
of efficiencies, its efficiency will be returned. If not, an
efficiency of unity will be returned.
* A ``dict`` mapping collider species to mole fractions. The overall
efficiency will be a weighted sum of the efficiencies of the collider
species, using the mole fractions as the weights. Collider species not
present in the set of efficiencies will be assumed to have an
efficiency of unity.
If collider is ``None`` or otherwise invalid, an efficiency of unity
will be returned.
"""
if isinstance(collider, dict):
# Assume collider is a dict mapping species to weights
efficiency = 0.0
for spec, frac in collider.iteritems():
try:
eff = self.efficiencies[spec]
except KeyError:
eff = 1.0
efficiency += eff * frac
efficiency /= sum(collider.values())
else:
# Assume collider is a single species
try:
efficiency = self.efficiencies[collider]
except KeyError:
efficiency = 1.0
return efficiency
def to_cti(self, reactantstr, arrow, productstr, indent=0):
rxnstr = reactantstr + ' + M' + arrow + productstr + ' + M'
prefix = ' '*(indent + 20)
lines = ['three_body_reaction({0!r}, {1},'.format(rxnstr, self.arrheniusHigh.rateStr())]
if self.efficiencies:
lines.append(prefix + 'efficiencies={0!r},'.format(self.efficiencyString()))
lines[-1] = lines[-1][:-1] + ')'
return '\n'.join(lines)
################################################################################
class Lindemann(ThirdBody):
"""
A kinetic model of a phenomenological rate coefficient k(T, P) using the
expression
.. math:: k(T,P) = k_\\infty(T) \\left[ \\frac{P_\\mathrm{r}}{1 + P_\\mathrm{r}} \\right] F
where
.. math::
P_\\mathrm{r} &= \\frac{k_0(T)}{k_\\infty(T)} [\\ce{M}]
k_0(T) &= A_0 T^{n_0} \\exp \\left( - \\frac{E_0}{RT} \\right)
k_\\infty(T) &= A_\\infty T^{n_\\infty} \\exp \\left( - \\frac{E_\\infty}{RT} \\right)
and :math:`[\\ce{M}] \\approx P/RT` is the concentration of the
bath gas. The Arrhenius expressions :math:`k_0(T)` and :math:`k_\\infty(T)`
represent the low-pressure and high-pressure limit kinetics, respectively.
The former is necessarily one reaction order higher than the latter. For
the Lindemann model, :math:`F = 1`. A collision efficiency can be used to
further correct the value of :math:`k(T,P)`.
The attributes are:
=============== ======================= ====================================
Attribute Type Description
=============== ======================= ====================================
`arrheniusLow` :class:`Arrhenius` The Arrhenius kinetics at the low-pressure limit
`arrheniusHigh` :class:`Arrhenius` The Arrhenius kinetics at the high-pressure limit
`efficiencies` ``dict`` A mapping of species to collider efficiencies
=============== ======================= ====================================
"""
def __init__(self, arrheniusLow=None, arrheniusHigh=None, efficiencies=None, Tmin=None, Tmax=None, Pmin=None, Pmax=None, comment=''):
ThirdBody.__init__(self, arrheniusHigh=arrheniusHigh, efficiencies=efficiencies, Tmin=Tmin, Tmax=Tmax, Pmin=Pmin, Pmax=Pmax, comment=comment)
self.arrheniusLow = arrheniusLow
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'Lindemann(\n'
lines = self.arrheniusHigh.toPrettyRepr().splitlines()
string += u' arrheniusHigh = {0}\n'.format(lines[0])
for line in lines[1:-1]:
string += u' {0}\n'.format(line)
string += u' ),\n'
lines = self.arrheniusLow.toPrettyRepr().splitlines()
string += u' arrheniusLow = {0}\n'.format(lines[0])
for line in lines[1:-1]:
string += u' {0}\n'.format(line)
string += u' ),\n'
if len(self.efficiencies) > 0:
string += u' efficiencies = {\n'
for species in sorted(self.efficiencies):
string += u' "{0}": {1:g},\n'.format(species, self.efficiencies[species])
string += u' },\n'
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.Pmin is not None: string += ' Pmin = {0!r},\n'.format(self.Pmin)
if self.Pmax is not None: string += ' Pmax = {0!r},\n'.format(self.Pmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __reduce__(self):
"""
A helper function used when pickling a Lindemann object.
"""
return (Lindemann, (self.arrheniusLow, self.arrheniusHigh, self.efficiencies, self.Tmin, self.Tmax, self.Pmin, self.Pmax, self.comment))
def to_cti(self, reactantstr, arrow, productstr, indent=0):
rxnstr = reactantstr + ' (+ M)' + arrow + productstr + ' (+ M)'
prefix = ' '*(indent + 17)
lines = ['falloff_reaction({0!r},'.format(rxnstr)]
lines.append(prefix + 'kf={0},'.format(self.arrheniusHigh.rateStr()))
lines.append(prefix + 'kf0={0},'.format(self.arrheniusLow.rateStr()))
if self.efficiencies:
lines.append(prefix + 'efficiencies={0!r},'.format(self.efficiencyString()))
lines[-1] = lines[-1][:-1] + ')'
return '\n'.join(lines)
################################################################################
class Troe(Lindemann):
"""
A kinetic model of a phenomenological rate coefficient k(T, P) using the
expression
.. math:: k(T,P) = k_\\infty(T) \\left[ \\frac{P_\\mathrm{r}}{1 + P_\\mathrm{r}} \\right] F
where
.. math::
P_\\mathrm{r} &= \\frac{k_0(T)}{k_\\infty(T)} [\\ce{M}]
k_0(T) &= A_0 T^{n_0} \\exp \\left( - \\frac{E_0}{RT} \\right)
k_\\infty(T) &= A_\\infty T^{n_\\infty} \\exp \\left( - \\frac{E_\\infty}{RT} \\right)
and :math:`[\\ce{M}] \\approx P/RT` is the concentration of the
bath gas. The Arrhenius expressions :math:`k_0(T)` and :math:`k_\\infty(T)`
represent the low-pressure and high-pressure limit kinetics, respectively.
The former is necessarily one reaction order higher than the latter. A
collision efficiency can be used to further correct the value of
:math:`k(T,P)`.
For the Troe model the parameter :math:`F` is computed via
.. math::
\\log F &= \\left\\{1 + \\left[ \\frac{\\log P_\\mathrm{r} + c}{n - d (\\log P_\\mathrm{r} + c)} \\right]^2 \\right\\}^{-1} \\log F_\\mathrm{cent}
c &= -0.4 - 0.67 \\log F_\\mathrm{cent}
n &= 0.75 - 1.27 \\log F_\\mathrm{cent}
d &= 0.14
F_\\mathrm{cent} &= (1 - \\alpha) \\exp \\left( -T/T_3 \\right) + \\alpha \\exp \\left( -T/T_1 \\right) + \\exp \\left( -T_2/T \\right)
The attributes are:
=============== ======================= ====================================
Attribute Type Description
=============== ======================= ====================================
`arrheniusLow` :class:`Arrhenius` The Arrhenius kinetics at the low-pressure limit
`arrheniusHigh` :class:`Arrhenius` The Arrhenius kinetics at the high-pressure limit
`efficiencies` ``dict`` A mapping of species to collider efficiencies
`alpha` :class:`Quantity` The :math:`\\alpha` parameter
`T1` :class:`Quantity` The :math:`T_1` parameter
`T2` :class:`Quantity` The :math:`T_2` parameter
`T3` :class:`Quantity` The :math:`T_3` parameter
=============== ======================= ====================================
"""
def __init__(self, arrheniusLow=None, arrheniusHigh=None, efficiencies=None, alpha=0.0, T3=0.0, T1=0.0, T2=None, Tmin=None, Tmax=None, Pmin=None, Pmax=None, comment=''):
Lindemann.__init__(self, arrheniusLow=arrheniusLow, arrheniusHigh=arrheniusHigh, efficiencies=efficiencies, Tmin=Tmin, Tmax=Tmax, Pmin=Pmin, Pmax=Pmax, comment=comment)
self.alpha = alpha
self.T3 = T3
self.T1 = T1
if T2 is not None:
self.T2 = T2
else:
self.T2 = None
def toPrettyRepr(self):
"""
Return a string representation of the reference that can be used to
reconstruct the object.
"""
string = u'Troe(\n'
lines = self.arrheniusHigh.toPrettyRepr().splitlines()
string += u' arrheniusHigh = {0}\n'.format(lines[0])
for line in lines[1:-1]:
string += u' {0}\n'.format(line)
string += u' ),\n'
lines = self.arrheniusLow.toPrettyRepr().splitlines()
string += u' arrheniusLow = {0}\n'.format(lines[0])
for line in lines[1:-1]:
string += u' {0}\n'.format(line)
string += u' ),\n'
string += u' alpha = {0!r},\n'.format(self.alpha)
string += u' T3 = {0!r},\n'.format(self.T3)
string += u' T1 = {0!r},\n'.format(self.T1)
if self.T2 is not None: string += u' T2 = {0!r},\n'.format(self.T2)
if len(self.efficiencies) > 0:
string += u' efficiencies = {\n'
for molecule in sorted(self.efficiencies):
string += u' "{0}": {1:g},\n'.format(molecule, self.efficiencies[molecule])
string += u' },\n'
if self.Tmin is not None: string += ' Tmin = {0!r},\n'.format(self.Tmin)
if self.Tmax is not None: string += ' Tmax = {0!r},\n'.format(self.Tmax)
if self.Pmin is not None: string += ' Pmin = {0!r},\n'.format(self.Pmin)
if self.Pmax is not None: string += ' Pmax = {0!r},\n'.format(self.Pmax)
if self.comment != '': string += ' comment = """{0}""",\n'.format(self.comment)
return string + u')'
def __reduce__(self):
"""
A helper function used when pickling a Troe object.
"""
return (Troe, (self.arrheniusLow, self.arrheniusHigh, self.efficiencies, self.alpha, self.T3, self.T1, self.T2, self.Tmin, self.Tmax, self.Pmin, self.Pmax, self.comment))
def to_cti(self, reactantstr, arrow, productstr, indent=0):
rxnstr = reactantstr + ' (+ M)' + arrow + productstr + ' (+ M)'
prefix = ' '*17
lines = ['falloff_reaction({0!r},'.format(rxnstr),
prefix + 'kf={0},'.format(self.arrheniusHigh.rateStr()),
prefix + 'kf0={0},'.format(self.arrheniusLow.rateStr())]
if self.T2:
troeArgs = 'A={0.alpha[0]}, T3={0.T3[0]}, T1={0.T1[0]}, T2={0.T2[0]}'.format(self)
else:
troeArgs = 'A={0.alpha[0]}, T3={0.T3[0]}, T1={0.T1[0]}'.format(self)
lines.append(prefix + 'falloff=Troe({0}),'.format(troeArgs))
if self.efficiencies:
lines.append(prefix + 'efficiencies={0!r},'.format(self.efficiencyString()))
# replace trailing comma
lines[-1] = lines[-1][:-1] + ')'
return '\n'.join(lines)
################################################################################
class TransportData(object):
geometryFlags = ['atom', 'linear', 'nonlinear']
def __init__(self, label, geometry, wellDepth, collisionDiameter,
dipoleMoment, polarizability, zRot, comment=None):
assert isinstance(label, types.StringTypes)
assert int(geometry) in (0,1,2)
self.label = label
self.geometry = self.geometryFlags[int(geometry)]
self.wellDepth = float(wellDepth)
self.collisionDiameter = float(collisionDiameter)
self.dipoleMoment = float(dipoleMoment)
self.polarizability = float(polarizability)
self.zRot = float(zRot)
self.comment = comment or '' # @todo: include this in the CTI
def __repr__(self):
return ('TransportData({label!r}, {geometry!r}, {wellDepth!r}, '
'{collisionDiameter!r}, {dipoleMoment!r}, {polarizability!r}, '
'{zRot!r}, {comment!r})').format(**self.__dict__)
def to_cti(self, indent=0):
prefix = ' '*(indent+18)
lines = ['gas_transport(geom={0!r},'.format(self.geometry),
prefix+'diam={0},'.format(self.collisionDiameter),
prefix+'well_depth={0},'.format(self.wellDepth)]
if self.dipoleMoment:
lines.append(prefix+'dipole={0},'.format(self.dipoleMoment))
if self.polarizability:
lines.append(prefix+'polar={0},'.format(self.polarizability))
if self.zRot:
lines.append(prefix+'rot_relax={0},'.format(self.zRot))
lines[-1] = lines[-1][:-1] + ')'
return '\n'.join(lines)
################################################################################
def fortFloat(s):
"""
Convert a string representation of a floating point value to a float,
allowing for some of the peculiarities of allowable Fortran representations.
"""
s = s.strip()
s = s.replace('D', 'E').replace('d', 'e')
s = s.replace('E ', 'E+').replace('e ', 'e+')
return float(s)
################################################################################
def readThermoEntry(entry, TintDefault):
"""
Read a thermodynamics `entry` for one species in a Chemkin file. Returns
the label of the species, the thermodynamics model as a :class:`MultiNASA`
object and the elemental composition of the species.
"""
lines = entry.splitlines()
identifier = lines[0][0:24].split()
species = identifier[0].strip()
if len(identifier) > 1:
note = ''.join(identifier[1:]).strip()
else:
note = ''
# Extract the NASA polynomial coefficients
# Remember that the high-T polynomial comes first!
try:
Tmin = fortFloat(lines[0][45:55])
Tmax = fortFloat(lines[0][55:65])
try:
Tint = fortFloat(lines[0][65:75])
except ValueError:
Tint = TintDefault
a0_high = fortFloat(lines[1][0:15])
a1_high = fortFloat(lines[1][15:30])
a2_high = fortFloat(lines[1][30:45])
a3_high = fortFloat(lines[1][45:60])
a4_high = fortFloat(lines[1][60:75])
a5_high = fortFloat(lines[2][0:15])
a6_high = fortFloat(lines[2][15:30])
a0_low = fortFloat(lines[2][30:45])
a1_low = fortFloat(lines[2][45:60])
a2_low = fortFloat(lines[2][60:75])
a3_low = fortFloat(lines[3][0:15])
a4_low = fortFloat(lines[3][15:30])
a5_low = fortFloat(lines[3][30:45])
a6_low = fortFloat(lines[3][45:60])
except (IndexError, ValueError) as err:
raise ChemkinError('Error while reading thermo entry for species {0}'.format(species))
elements = lines[0][24:44]
composition = {}
for i in range(4):
symbol = elements[5*i:5*i+2].strip()
count = elements[5*i+2:5*i+5].strip()
if not symbol:
continue
try:
count = int(float(count))
if count:
composition[symbol.capitalize()] = count
except ValueError:
pass
# Construct and return the thermodynamics model
thermo = MultiNASA(
polynomials = [
NASA(Tmin=(Tmin,"K"), Tmax=(Tint,"K"), coeffs=[a0_low, a1_low, a2_low, a3_low, a4_low, a5_low, a6_low]),
NASA(Tmin=(Tint,"K"), Tmax=(Tmax,"K"), coeffs=[a0_high, a1_high, a2_high, a3_high, a4_high, a5_high, a6_high])
],
Tmin = (Tmin,"K"),
Tmax = (Tmax,"K"),
)
return species, thermo, composition, note
################################################################################
def readKineticsEntry(entry, speciesDict, energyUnits, moleculeUnits):
"""
Read a kinetics `entry` for a single reaction as loaded from a Chemkin
file. The associated mapping of labels to species `speciesDict` should also
be provided. Returns a :class:`Reaction` object with the reaction and its
associated kinetics.
"""
lines = entry.strip().splitlines()
# The first line contains the reaction equation and a set of modified Arrhenius parameters
tokens = lines[0].split()
A = float(tokens[-3])
n = float(tokens[-2])
Ea = float(tokens[-1])
reaction = ''.join(tokens[:-3])
thirdBody = False
# Split the reaction equation into reactants and products
if '<=>' in reaction:
reversible = True
reactants, products = reaction.split('<=>')
elif '=>' in reaction:
reversible = False
reactants, products = reaction.split('=>')
elif '=' in reaction:
reversible = True
reactants, products = reaction.split('=')
else:
raise ChemkinError("Failed to find reactant/product delimiter in reaction string.")
if '(+M)' in reactants: reactants = reactants.replace('(+M)','')
if '(+m)' in reactants: reactants = reactants.replace('(+m)','')
if '(+M)' in products: products = products.replace('(+M)','')
if '(+m)' in products: products = products.replace('(+m)','')
# Create a new Reaction object for this reaction
reaction = Reaction(reactants=[], products=[], reversible=reversible)
# Convert the reactants and products to Species objects using the speciesDict
for reactant in reactants.split('+'):
reactant = reactant.strip()
stoichiometry = 1
if reactant[0].isdigit():
# This allows for reactions to be of the form 2A=B+C instead of A+A=B+C
# The implementation below assumes an integer between 0 and 9, inclusive
stoichiometry = int(reactant[0])
reactant = reactant[1:]
if reactant == 'M' or reactant == 'm':
thirdBody = True
elif reactant not in speciesDict:
raise ChemkinError('Unexpected reactant "{0}" in reaction {1}.'.format(reactant, reaction))
else:
for i in range(stoichiometry):
reaction.reactants.append(speciesDict[reactant])
for product in products.split('+'):
product = product.strip()
stoichiometry = 1
if product[0].isdigit():
# This allows for reactions to be of the form A+B=2C instead of A+B=C+C
# The implementation below assumes an integer between 0 and 9, inclusive
stoichiometry = int(product[0])
product = product[1:]
if product.upper() == 'M' or product == 'm':
pass
elif product not in speciesDict:
raise ChemkinError('Unexpected product "{0}" in reaction {1}.'.format(product, reaction))
else:
for i in range(stoichiometry):
reaction.products.append(speciesDict[product])
# Determine the appropriate units for k(T) and k(T,P) based on the number of reactants
# This assumes elementary kinetics for all reactions
if len(reaction.reactants) + (1 if thirdBody else 0) == 3:
kunits = "cm^6/(mol^2*s)"
klow_units = "cm^9/(mol^3*s)"
elif len(reaction.reactants) + (1 if thirdBody else 0) == 2:
kunits = "cm^3/(mol*s)"
klow_units = "cm^6/(mol^2*s)"
elif len(reaction.reactants) + (1 if thirdBody else 0) == 1:
kunits = "s^-1"
klow_units = "cm^3/(mol*s)"
else:
raise ChemkinError('Invalid number of reactant species for reaction {0}.'.format(reaction))
# The rest of the first line contains the high-P limit Arrhenius parameters (if available)
#tokens = lines[0][52:].split()
tokens = lines[0].split()[1:]
arrheniusHigh = Arrhenius(
A = (A,kunits),
n = n,
Ea = (Ea, energyUnits),
T0 = (1,"K"),
)
if len(lines) == 1:
# If there's only one line then we know to use the high-P limit kinetics as-is
reaction.kinetics = arrheniusHigh
else:
# There's more kinetics information to be read
arrheniusLow = None
troe = None
chebyshev = None
pdepArrhenius = None
efficiencies = {}
chebyshevCoeffs = []
# Note that the subsequent lines could be in any order
for line in lines[1:]:
tokens = line.split('/')
if 'DUP' in line or 'dup' in line:
# Duplicate reaction
reaction.duplicate = True
elif 'LOW' in line or 'low' in line:
# Low-pressure-limit Arrhenius parameters
tokens = tokens[1].split()
arrheniusLow = Arrhenius(
A = (float(tokens[0].strip()),klow_units),
n = float(tokens[1].strip()),
Ea = (float(tokens[2].strip()),"kcal/mol"),
T0 = (1,"K"),
)
elif 'TROE' in line or 'troe' in line:
# Troe falloff parameters
tokens = tokens[1].split()
alpha = float(tokens[0].strip())
T3 = float(tokens[1].strip())
T1 = float(tokens[2].strip())
try:
T2 = float(tokens[3].strip())
except (IndexError, ValueError):
T2 = None
troe = Troe(
alpha = (alpha,''),
T3 = (T3,"K"),
T1 = (T1,"K"),
T2 = (T2,"K") if T2 is not None else None,
)
elif 'CHEB' in line or 'cheb' in line:
# Chebyshev parameters
if chebyshev is None:
chebyshev = Chebyshev()
tokens = [t.strip() for t in tokens]
if 'TCHEB' in line:
index = tokens.index('TCHEB')
tokens2 = tokens[index+1].split()
chebyshev.Tmin = float(tokens2[0].strip())
chebyshev.Tmax = float(tokens2[1].strip())
if 'PCHEB' in line:
index = tokens.index('PCHEB')
tokens2 = tokens[index+1].split()
chebyshev.Pmin = (float(tokens2[0].strip()), 'atm')
chebyshev.Pmax = (float(tokens2[1].strip()), 'atm')
if 'TCHEB' in line or 'PCHEB' in line:
pass
elif chebyshev.degreeT == 0 or chebyshev.degreeP == 0:
tokens2 = tokens[1].split()
chebyshev.degreeT = int(float(tokens2[0].strip()))
chebyshev.degreeP = int(float(tokens2[1].strip()))
chebyshev.coeffs = np.zeros((chebyshev.degreeT,chebyshev.degreeP), np.float64)
else:
tokens2 = tokens[1].split()
chebyshevCoeffs.extend([float(t.strip()) for t in tokens2])
elif 'PLOG' in line or 'plog' in line:
# Pressure-dependent Arrhenius parameters
if pdepArrhenius is None:
pdepArrhenius = []
tokens = tokens[1].split()
pdepArrhenius.append([float(tokens[0].strip()), Arrhenius(
A = (float(tokens[1].strip()),kunits),
n = float(tokens[2].strip()),
Ea = (float(tokens[3].strip()),"kcal/mol"),
T0 = (1,"K"),
)])
else:
# Assume a list of collider efficiencies
for collider, efficiency in zip(tokens[0::2], tokens[1::2]):
efficiencies[collider.strip()] = float(efficiency.strip())
# Decide which kinetics to keep and store them on the reaction object
# Only one of these should be true at a time!
if chebyshev is not None:
if chebyshev.Tmin is None or chebyshev.Tmax is None:
raise ChemkinError('Missing TCHEB line for reaction {0}'.format(reaction))
if chebyshev.Pmin is None or chebyshev.Pmax is None:
raise ChemkinError('Missing PCHEB line for reaction {0}'.format(reaction))
index = 0
for t in range(chebyshev.degreeT):
for p in range(chebyshev.degreeP):
chebyshev.coeffs[t,p] = chebyshevCoeffs[index]
index += 1
reaction.kinetics = chebyshev
elif pdepArrhenius is not None:
reaction.kinetics = PDepArrhenius(
pressures = ([P for P, arrh in pdepArrhenius],"atm"),
arrhenius = [arrh for P, arrh in pdepArrhenius],
)
elif troe is not None:
troe.arrheniusHigh = arrheniusHigh
troe.arrheniusLow = arrheniusLow
troe.efficiencies = efficiencies
reaction.kinetics = troe
elif arrheniusLow is not None:
reaction.kinetics = Lindemann(arrheniusHigh=arrheniusHigh, arrheniusLow=arrheniusLow)
reaction.kinetics.efficiencies = efficiencies
elif thirdBody:
reaction.kinetics = ThirdBody(arrheniusHigh=arrheniusHigh)
reaction.kinetics.efficiencies = efficiencies
elif reaction.duplicate:
reaction.kinetics = arrheniusHigh
else:
raise ChemkinError('Unable to determine pressure-dependent kinetics for reaction {0}.'.format(reaction))
return reaction
################################################################################
def loadChemkinFile(path, speciesList=None):
"""
Load a Chemkin input file to `path` on disk, returning lists of the species
and reactions in the Chemkin file.
"""
speciesDict = {}
if speciesList is None:
speciesList = []
else:
for species in speciesList:
speciesDict[species.label] = species
reactionList = []
transportLines = []
def removeCommentFromLine(line):
if '!' in line:
index = line.index('!')
comment = line[index+1:-1]
line = line[0:index] + '\n'
return line, comment
else:
comment = ''
return line, comment
with open(path, 'r') as f:
line = f.readline()
while line != '':
line = removeCommentFromLine(line)[0]
line = line.strip()
tokens = line.split()
if 'SPECIES' in line:
# List of species identifiers
index = tokens.index('SPECIES')
tokens = tokens[index+1:]
while 'END' not in tokens:
line = f.readline()
line = removeCommentFromLine(line)[0]
line = line.strip()
tokens.extend(line.split())
for token in tokens:
if token == 'END':
break
if token in speciesDict:
species = speciesDict[token]
else:
species = Species(label=token)
speciesDict[token] = species
speciesList.append(species)
elif 'THERM' in line:
# List of thermodynamics (hopefully one per species!)
line = f.readline()
TintDefault = float(line.split()[1])
thermo = ''
while line != '' and 'END' not in line:
line = removeCommentFromLine(line)[0]
if len(line) >= 80:
if line[79] in ['1', '2', '3', '4']:
thermo += line
if line[79] == '4':
label, thermo, comp, note = readThermoEntry(thermo, TintDefault)
try:
speciesDict[label].thermo = thermo
speciesDict[label].composition = comp
speciesDict[label].note = note
except KeyError:
logging.warning('Skipping unexpected species "{0}" while reading thermodynamics entry.'.format(label))
thermo = ''
line = f.readline()
elif 'REACTIONS' in line:
# Reactions section
energyUnits = 'CAL/MOL'
moleculeUnits = 'MOLES'
try:
energyUnits = tokens[1]
moleculeUnits = tokens[2]
except IndexError:
pass
ENERGY_UNITS = UNIT_OPTIONS[energyUnits]
QUANTITY_UNITS = UNIT_OPTIONS[moleculeUnits]
kineticsList = []
commentsList = []
kinetics = ''
comments = ''
line = f.readline()
while line != '' and 'END' not in line:
lineStartsWithComment = line.startswith('!')
line, comment = removeCommentFromLine(line)
line = line.strip(); comment = comment.strip()
if 'rev' in line or 'REV' in line:
# can no longer name reactants rev...
line = f.readline()
if '=' in line and not lineStartsWithComment:
# Finish previous record
kineticsList.append(kinetics)
commentsList.append(comments)
kinetics = ''
comments = ''
if line: kinetics += line + '\n'
if comment: comments += comment + '\n'
line = f.readline()
# Don't forget the last reaction!
if kinetics.strip() != '':
kineticsList.append(kinetics)
commentsList.append(comments)
if kineticsList[0] == '' and commentsList[-1] == '':
# True for Chemkin files generated from RMG-Py
kineticsList.pop(0)
commentsList.pop(-1)
elif kineticsList[0] == '' and commentsList[0] == '':
# True for Chemkin files generated from RMG-Java
kineticsList.pop(0)
commentsList.pop(0)
else:
# In reality, comments can occur anywhere in the Chemkin
# file (e.g. either or both of before and after the
# reaction equation)
# If we can't tell what semantics we are using, then just
# throw the comments away
# (This is better than failing to load the Chemkin file at
# all, which would likely occur otherwise)
if kineticsList[0] == '':
kineticsList.pop(0)
if len(kineticsList) != len(commentsList):
commentsList = ['' for kinetics in kineticsList]
for kinetics, comments in zip(kineticsList, commentsList):
reaction = readKineticsEntry(kinetics, speciesDict, energyUnits, moleculeUnits)
reactionList.append(reaction)
elif 'TRAN' in line:
line = f.readline()
while 'END' not in line:
transportLines.append(line)
line = f.readline()
# Check for marked (and unmarked!) duplicate reactions
# Raise exception for unmarked duplicate reactions
for index1 in range(len(reactionList)):
reaction1 = reactionList[index1]
for index2 in range(index1+1, len(reactionList)):
reaction2 = reactionList[index2]
if reaction1.reactants == reaction2.reactants and reaction1.products == reaction2.products:
if reaction1.duplicate and reaction2.duplicate:
pass
elif reaction1.kinetics.isPressureDependent() == reaction2.kinetics.isPressureDependent():
# If both reactions are pressure-independent or both are pressure-dependent, then they need duplicate tags
# Chemkin treates pdep and non-pdep reactions as different, so those are okay
raise ChemkinError('Encountered unmarked duplicate reaction {0}.'.format(reaction1))
index = 0
for reaction in reactionList:
index += 1
reaction.index = index
if transportLines:
parseTransportData(transportLines, speciesList)
return speciesList, reactionList
################################################################################
def parseTransportData(lines, speciesList):
"""
Parse the Chemkin-format transport data in ``lines`` (a list of strings)
and add that transport data to the species in ``speciesList``.
"""
speciesDict = dict((species.label, species) for species in speciesList)
for line in lines:
line = line.strip()
if not line or line.startswith('!'):
continue
if line.startswith('END'):
break
data = line.split()
if len(data) < 7:
raise ChemkinError('Unable to parse transport data: not enough parameters')
if len(data) >= 8:
# comment may contain spaces. Rejoin into a single field.
comment = ''.join(data[7:]).lstrip('!')
data = data[:7] + [comment]
speciesName = data[0]
if speciesName in speciesDict:
speciesDict[speciesName].transport = TransportData(*data)
################################################################################
def writeCTI(species,
reactions=None,
header=None,
name='gas',
transportModel='Mix',
outName='mech.cti'):
delimiterLine = '#' + '-'*79
haveTransport = True
speciesNameLength = 1
elements = set()
for s in species:
if not s.transport:
haveTransport = False
if s.composition is None:
raise ChemkinError('No thermo data found for species: {0!r}'.format(s.label))
elements.update(s.composition)
speciesNameLength = max(speciesNameLength, len(s.label))
speciesNames = ['']
for i,s in enumerate(species):
if i and not i % 5:
speciesNames.append(' '*21)
speciesNames[-1] += '{0:{1}s}'.format(s.label, speciesNameLength+2)
speciesNames = '\n'.join(speciesNames).strip()
lines = []
if header:
lines.extend(header)
# Write the gas definition
lines.append("units(length='cm', time='s', quantity={0!r}, act_energy={1!r})".format(QUANTITY_UNITS, ENERGY_UNITS))
lines.append('')
lines.append('ideal_gas(name={0!r},'.format(name))
lines.append(' elements="{0}",'.format(' '.join(elements)))
lines.append(' species="""{0}""",'.format(speciesNames))
if reactions:
lines.append(" reactions='all',")
if haveTransport:
lines.append(" transport={0!r},".format(transportModel))
lines.append(' initial_state=state(temperature=300.0, pressure=OneAtm))')
lines.append('')
# Write the individual species data
lines.append(delimiterLine)
lines.append('# Species data')
lines.append(delimiterLine)
lines.append('')
for s in species:
lines.append(s.to_cti())
# Write the reactions
lines.append(delimiterLine)
lines.append('# Reaction data')
lines.append(delimiterLine)
for i,r in enumerate(reactions):
lines.append('\n# Reaction {0}'.format(i+1))
lines.append(r.to_cti())
lines.append('')
f = open(outName, 'w')
f.write('\n'.join(lines))
################################################################################
def showHelp():
print """
ck2cti.py: Convert Chemkin-format mechanisms to Cantera input files (.cti)
If the output file name is not given, an output file with the same name as the
input file, with the extension changed to '.cti'.
Usage:
ck2cti --input=<filename>
[--thermo=<filename>]
[--transport=<filename>]
[--id=<phase-id>]
[--output=<filename>]
[-d | --debug]
Example:
ck2cti --input=chem.inp --thermo=therm.dat --transport=tran.dat
"""
################################################################################
def convertMech(inputFile, thermoFile=None,
transportFile=None, phaseName='gas',
outName=None):
# Read input mechanism files
species, reactions = loadChemkinFile(inputFile)
if thermoFile:
species, _ = loadChemkinFile(thermoFile, species)
if transportFile:
lines = open(transportFile).readlines()
parseTransportData(lines, species)
if not outName:
outName = os.path.splitext(inputFile)[0] + '.cti'
# Write output file
writeCTI(species, reactions, name=phaseName, outName=outName)
print 'Wrote CTI mechanism file to {0!r}.'.format(outName)
print 'Mechanism contains {0} species and {1} reactions.'.format(len(species), len(reactions))
################################################################################
if __name__ == '__main__':
import getopt
import sys
import os.path
longOptions = ['input=', 'thermo=', 'transport=', 'id=', 'output=',
'help', 'debug']
try:
optlist, args = getopt.getopt(sys.argv[1:], 'dh', longOptions)
options = dict()
for o,a in optlist:
options[o] = a
if args:
raise getopt.GetoptError('Unexpected command line option: ' +
repr(' '.join(args)))
except getopt.GetoptError as e:
print 'ck2cti.py: Error parsing arguments:'
print e
print 'Run "ck2cti.py --help" to see usage help.'
sys.exit(1)
if not options or '-h' in options or '--help' in options:
showHelp()
sys.exit(0)
if '--input' in options:
inputFile = options['--input']
else:
print 'Error: no mechanism input file specified'
sys.exit(1)
if '--output' in options:
outName = options['--output']
if not outName.endswith('.cti'):
outName += '.cti'
else:
outName = None
thermoFile = options.get('--thermo')
transportFile = options.get('--transport')
phaseName = options.get('--id', 'gas')
convertMech(inputFile, thermoFile, transportFile, phaseName, outName)