Blowers Masel reaction rate type depends on the enthalpy of reaction. More...

#include <BlowersMaselRate.h>

Inheritance diagram for BlowersMaselRate:

Collaboration diagram for BlowersMaselRate:

Public Member Functions
	BlowersMaselRate ()
	Default constructor. More...

	BlowersMaselRate (double A, double b, double Ea0, double w)
	Constructor. More...

	BlowersMaselRate (const AnyMap &node, const UnitStack &rate_units={})

unique_ptr< MultiRateBase >	newMultiRate () const override
	Create a rate evaluator for reactions of a particular derived type. More...

virtual const std::string	type () const override
	String identifying reaction rate specialization. More...

virtual void	setContext (const Reaction &rxn, const Kinetics &kin) override
	Set context of reaction rate evaluation. More...

double	evalRate (double logT, double recipT) const
	Evaluate reaction rate. More...

void	updateFromStruct (const BlowersMaselData &shared_data)
	Update information specific to reaction. More...

double	evalFromStruct (const BlowersMaselData &shared_data) const
	Evaluate reaction rate. More...

double	ddTScaledFromStruct (const BlowersMaselData &shared_data) const
	Evaluate derivative of reaction rate with respect to temperature divided by reaction rate. More...

virtual double	activationEnergy () const override
	Return the activation energy Ea [J/kmol] The value corresponds to the constant specified by input parameters;. More...

double	bondEnergy () const
	Return the bond dissociation energy w [J/kmol]. More...

double	deltaH () const
	Return current enthalpy change of reaction [J/kmol]. More...

void	setDeltaH (double deltaH)
	Set current enthalpy change of reaction [J/kmol]. More...

Public Member Functions inherited from ArrheniusBase
	ArrheniusBase ()
	Default constructor. More...

	ArrheniusBase (double A, double b, double Ea)
	Constructor. More...

	ArrheniusBase (const AnyValue &rate, const UnitSystem &units, const UnitStack &rate_units)
	Constructor based on AnyValue content. More...

	ArrheniusBase (const AnyMap &node, const UnitStack &rate_units={})

void	setRateParameters (const AnyValue &rate, const UnitSystem &units, const UnitStack &rate_units)
	Perform object setup based on AnyValue node information. More...

void	getRateParameters (AnyMap &node) const
	Return parameters. More...

virtual void	setParameters (const AnyMap &node, const UnitStack &rate_units) override
	Set parameters. More...

virtual void	getParameters (AnyMap &node) const override
	Get parameters. More...

virtual void	check (const std::string &equation, const AnyMap &node) override
	Check rate expression. More...

virtual void	validate (const std::string &equation, const Kinetics &kin) override
	Validate the reaction rate expression. More...

virtual double	preExponentialFactor () const
	Return the pre-exponential factor A (in m, kmol, s to powers depending on the reaction order) More...

virtual double	temperatureExponent () const
	Return the temperature exponent b More...

const Units &	rateUnits () const

double	order () const
	Return reaction order associated with the reaction rate. More...

void	setRateUnits (const UnitStack &rate_units)
	Set units of the reaction rate expression. More...

bool	allowNegativePreExponentialFactor () const
	Get flag indicating whether negative A values are permitted. More...

void	setAllowNegativePreExponentialFactor (bool value)
	Set flag indicating whether negative A values are permitted. More...

Public Member Functions inherited from ReactionRate
	ReactionRate (const ReactionRate &other)

ReactionRate &	operator= (const ReactionRate &other)

AnyMap	parameters () const
	Return the parameters such that an identical Reaction could be reconstructed using the newReaction() function. More...

virtual void	validate (const std::string &equation)
	Validate the reaction rate expression (legacy call) More...

size_t	rateIndex () const
	Reaction rate index within kinetics evaluator. More...

void	setRateIndex (size_t idx)
	Set reaction rate index within kinetics evaluator. More...

double	eval (double T)
	Evaluate reaction rate based on temperature. More...

double	eval (double T, double extra)
	Evaluate reaction rate based on temperature and an extra parameter. More...

double	eval (double T, const std::vector< double > &extra)
	Evaluate reaction rate based on temperature and an extra vector parameter. More...

Protected Member Functions
double	effectiveActivationEnergy_R (double deltaH_R) const
	Return the effective activation energy (a function of the delta H of reaction) divided by the gas constant (that is, the activation temperature) [K]. More...

Protected Attributes
std::vector< std::pair< size_t, double > >	m_stoich_coeffs
	Pairs of species indices and multiplers to calculate enthalpy change. More...

double	m_deltaH_R
	enthalpy change of reaction (in temperature units) More...

Protected Attributes inherited from ArrheniusBase
bool	m_negativeA_ok
	Flag indicating whether negative A values are permitted. More...

double	m_A
	Pre-exponential factor. More...

double	m_b
	Temperature exponent. More...

double	m_Ea_R
	Activation energy (in temperature units) More...

double	m_E4_R
	Optional 4th energy parameter (in temperature units) More...

double	m_logA
	Logarithm of pre-exponential factor. More...

double	m_order
	Reaction order. More...

std::string	m_A_str = "A"
	The string for temperature exponent. More...

std::string	m_b_str = "b"
	The string for temperature exponent. More...

std::string	m_Ea_str = "Ea"
	The string for activation energy. More...

std::string	m_E4_str = ""
	The string for an optional 4th parameter. More...

Units	m_rate_units
	Reaction rate units. More...

Protected Attributes inherited from ReactionRate
AnyMap	m_input
	Input data used for specific models. More...

size_t	m_rate_index
	Index of reaction rate within kinetics evaluator. More...

Detailed Description

Blowers Masel reaction rate type depends on the enthalpy of reaction.

The Blowers Masel approximation is written by Paul Blowers, Rich Masel (DOI: https://doi.org/10.1002/aic.690461015) to adjust the activation energy based on enthalpy change of a reaction:

\begin{eqnarray*} E_a &=& 0\; \text{if }\Delta H < -4E_0 \\ E_a &=& \Delta H\; \text{if }\Delta H > 4E_0 \\ E_a &=& \frac{(w + \Delta H / 2)(V_P - 2w + \Delta H)^2}{(V_P^2 - 4w^2 + (\Delta H)^2)}\; \text{Otherwise} \end{eqnarray*}

where

\[ V_P = \frac{2w (w + E_0)}{w - E_0}, \]

\( w \) is the average bond dissociation energy of the bond breaking and that being formed in the reaction. Since the expression is very insensitive to \( w \) for \( w >= 2 E_0 \), \( w \) can be approximated to an arbitrary high value like 1000 kJ/mol.

After the activation energy is determined by Blowers-Masel approximation, it can be plugged into Arrhenius function to calculate the rate constant.

\[ k_f = A T^b \exp (-E_a/RT) \]

Definition at line 70 of file BlowersMaselRate.h.

Constructor & Destructor Documentation

◆ BlowersMaselRate() [1/3]

BlowersMaselRate ( )

Default constructor.

Definition at line 46 of file BlowersMaselRate.cpp.

References ArrheniusBase::m_E4_str, and ArrheniusBase::m_Ea_str.

◆ BlowersMaselRate() [2/3]

BlowersMaselRate	(	double	A,
		double	b,
		double	Ea0,
		double	w
	)

Constructor.

Parameters

A	Pre-exponential factor. The unit system is (kmol, m, s); actual units depend on the reaction order and the dimensionality (surface or bulk).
b	Temperature exponent (non-dimensional)
Ea0	Intrinsic activation energy in energy units [J/kmol]
w	Average bond dissociation energy of the bond being formed and broken in the reaction, in energy units [J/kmol]

Definition at line 53 of file BlowersMaselRate.cpp.

◆ BlowersMaselRate() [3/3]

BlowersMaselRate	(	const AnyMap &	node,
		const UnitStack &	rate_units = `{}`
	)

inlineexplicit

Definition at line 87 of file BlowersMaselRate.h.

Member Function Documentation

◆ newMultiRate()

unique_ptr< MultiRateBase > newMultiRate ( ) const

inlineoverridevirtual

Create a rate evaluator for reactions of a particular derived type.

Derived classes usually implement this as:

unique_ptr<MultiRateBase> newMultiRate() const override {

return unique_ptr<MultiRateBase>(new MultiRate<RateType, DataType>);

Cantera::BlowersMaselRate::newMultiRate

unique_ptr< MultiRateBase > newMultiRate() const override

Create a rate evaluator for reactions of a particular derived type.

Definition: BlowersMaselRate.h:93

where RateType is the derived class name and DataType is the corresponding container for parameters needed to evaluate reactions of that type.

Reimplemented from ReactionRate.

Definition at line 93 of file BlowersMaselRate.h.

◆ type()

virtual const std::string type ( ) const

inlineoverridevirtual

String identifying reaction rate specialization.

Implements ReactionRate.

Definition at line 97 of file BlowersMaselRate.h.

◆ setContext()

void setContext	(	const Reaction &	rxn,
		const Kinetics &	kin
	)

overridevirtual

Set context of reaction rate evaluation.

Parameters

rxn	Reaction object associated with rate
kin	Kinetics object used for rate evaluation This method allows for passing of information specific to the associated reaction when a ReactionRate object is added a MultiRate reaction evaluator.

Reimplemented from ReactionRate.

Definition at line 70 of file BlowersMaselRate.cpp.

References Kinetics::kineticsSpeciesIndex(), BlowersMaselRate::m_stoich_coeffs, Reaction::products, and Reaction::reactants.

◆ evalRate()

double evalRate	(	double	logT,
		double	recipT
	)		const

inline

Evaluate reaction rate.

Definition at line 104 of file BlowersMaselRate.h.

References BlowersMaselRate::effectiveActivationEnergy_R(), ArrheniusBase::m_A, ArrheniusBase::m_b, and BlowersMaselRate::m_deltaH_R.

◆ updateFromStruct()

void updateFromStruct ( const BlowersMaselData & shared_data )

inline

Update information specific to reaction.

Definition at line 110 of file BlowersMaselRate.h.

References Cantera::GasConstant, BlowersMaselRate::m_deltaH_R, BlowersMaselRate::m_stoich_coeffs, BlowersMaselData::partialMolarEnthalpies, and BlowersMaselData::ready.

◆ evalFromStruct()

double evalFromStruct ( const BlowersMaselData & shared_data ) const

inline

Evaluate reaction rate.

Parameters

shared_data data shared by all reactions of a given type

Definition at line 124 of file BlowersMaselRate.h.

References BlowersMaselRate::effectiveActivationEnergy_R(), ReactionData::logT, ArrheniusBase::m_A, ArrheniusBase::m_b, BlowersMaselRate::m_deltaH_R, and ReactionData::recipT.

◆ ddTScaledFromStruct()

double ddTScaledFromStruct ( const BlowersMaselData & shared_data ) const

Evaluate derivative of reaction rate with respect to temperature divided by reaction rate.

This method does not consider potential changes due to a changed reaction enthalpy. A corresponding warning is raised.

Parameters

shared_data data shared by all reactions of a given type

Definition at line 62 of file BlowersMaselRate.cpp.

References BlowersMaselRate::effectiveActivationEnergy_R(), ArrheniusBase::m_b, BlowersMaselRate::m_deltaH_R, ReactionData::recipT, and Cantera::warn_user().

◆ effectiveActivationEnergy_R()

double effectiveActivationEnergy_R ( double deltaH_R ) const

inlineprotected

Return the effective activation energy (a function of the delta H of reaction) divided by the gas constant (that is, the activation temperature) [K].

The enthalpy change of reaction is not an independent parameter

Definition at line 142 of file BlowersMaselRate.h.

References ArrheniusBase::m_E4_R, and ArrheniusBase::m_Ea_R.

Referenced by BlowersMaselRate::activationEnergy(), BlowersMaselRate::ddTScaledFromStruct(), BlowersMaselRate::evalFromStruct(), and BlowersMaselRate::evalRate().

◆ activationEnergy()

virtual double activationEnergy ( ) const

inlineoverridevirtual

Return the activation energy Ea [J/kmol] The value corresponds to the constant specified by input parameters;.

Class specializations may provide alternate definitions that describe an effective activation energy that depends on the thermodynamic state.

Reimplemented from ArrheniusBase.

Definition at line 157 of file BlowersMaselRate.h.

References BlowersMaselRate::effectiveActivationEnergy_R(), Cantera::GasConstant, and BlowersMaselRate::m_deltaH_R.

◆ bondEnergy()

double bondEnergy ( ) const

inline

Return the bond dissociation energy w [J/kmol].

Definition at line 162 of file BlowersMaselRate.h.

References Cantera::GasConstant, and ArrheniusBase::m_E4_R.

◆ deltaH()

double deltaH ( ) const

inline

Return current enthalpy change of reaction [J/kmol].

Definition at line 167 of file BlowersMaselRate.h.

References Cantera::GasConstant, and BlowersMaselRate::m_deltaH_R.

Referenced by BlowersMaselRate::setDeltaH().

◆ setDeltaH()

void setDeltaH ( double deltaH )

inline

Set current enthalpy change of reaction [J/kmol].

used for testing purposes only; note that this quantity is not an independent variable and will be overwritten during an update of the state.

Warning: This method is an experimental part of the Cantera API and may be changed or removed without notice.

Definition at line 179 of file BlowersMaselRate.h.

References BlowersMaselRate::deltaH(), Cantera::GasConstant, and BlowersMaselRate::m_deltaH_R.

Member Data Documentation

◆ m_stoich_coeffs

std::vector<std::pair<size_t, double> > m_stoich_coeffs

protected

Pairs of species indices and multiplers to calculate enthalpy change.

Definition at line 185 of file BlowersMaselRate.h.

Referenced by BlowersMaselRate::setContext(), and BlowersMaselRate::updateFromStruct().

◆ m_deltaH_R

double m_deltaH_R

protected

enthalpy change of reaction (in temperature units)

Definition at line 187 of file BlowersMaselRate.h.

Referenced by BlowersMaselRate::activationEnergy(), BlowersMaselRate::ddTScaledFromStruct(), BlowersMaselRate::deltaH(), BlowersMaselRate::evalFromStruct(), BlowersMaselRate::evalRate(), BlowersMaselRate::setDeltaH(), and BlowersMaselRate::updateFromStruct().

The documentation for this class was generated from the following files:

Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ BlowersMaselRate() [1/3]

◆ BlowersMaselRate() [2/3]

◆ BlowersMaselRate() [3/3]

Member Function Documentation

◆ newMultiRate()

◆ type()

◆ setContext()

◆ evalRate()

◆ updateFromStruct()

◆ evalFromStruct()

◆ ddTScaledFromStruct()

◆ effectiveActivationEnergy_R()

◆ activationEnergy()

◆ bondEnergy()

◆ deltaH()

◆ setDeltaH()

Member Data Documentation

◆ m_stoich_coeffs

◆ m_deltaH_R