Troe Class Reference

The 3- or 4-parameter Troe falloff parameterization. More...

#include <Falloff.h>

Inheritance diagram for Troe:

Collaboration diagram for Troe:

Public Member Functions
	Troe ()
	Constructor. More...
virtual void	init (const vector_fp &c)
	Initialization of the object. More...
virtual void	updateTemp (doublereal T, doublereal *work) const
	Update the temperature parameters in the representation. More...
virtual doublereal	F (doublereal pr, const doublereal *work) const
	The falloff function. More...
virtual size_t	workSize ()
	The size of the work array required. More...
virtual std::string	type () const
	Return a string representing the type of the Falloff parameterization. More...
virtual int	getType () const
	Return an integer representing the type of the Falloff parameterization. More...
virtual size_t	nParameters () const
	Returns the number of parameters used by this parameterization. More...
virtual void	getParameters (double *params) const
	Sets params to contain, in order,. More...

Protected Attributes
doublereal	m_a
	parameter a in the 4-parameter Troe falloff function. Dimensionless More...
doublereal	m_rt3
	parameter 1/T_3 in the 4-parameter Troe falloff function. [K^-1] More...
doublereal	m_rt1
	parameter 1/T_1 in the 4-parameter Troe falloff function. [K^-1] More...
doublereal	m_t2
	parameter T_2 in the 4-parameter Troe falloff function. [K] More...

Detailed Description

The 3- or 4-parameter Troe falloff parameterization.

The falloff function defines the value of \( F \) in the following rate expression

\[ k = k_{\infty} \left( \frac{P_r}{1 + P_r} \right) F \]

where

\[ P_r = \frac{k_0 [M]}{k_{\infty}} \]

This parameterization is defined by

\[ F = F_{cent}^{1/(1 + f_1^2)} \]

where

\[ F_{cent} = (1 - A)\exp(-T/T_3) + A \exp(-T/T_1) + \exp(-T_2/T) \]

\[ f_1 = (\log_{10} P_r + C) / \left(N - 0.14 (\log_{10} P_r + C)\right) \]

\[ C = -0.4 - 0.67 \log_{10} F_{cent} \]

\[ N = 0.75 - 1.27 \log_{10} F_{cent} \]

• If \( T_3 \) is zero, then the corresponding term is set to zero.
• If \( T_1 \) is zero, then the corresponding term is set to zero.
• If \( T_2 \) is zero, then the corresponding term is set to zero.

Definition at line 133 of file Falloff.h.

Constructor & Destructor Documentation

Troe()

Troe ( )

inline

Constructor.

Definition at line 137 of file Falloff.h.

Member Function Documentation

init()

void init ( const vector_fp &  c )

virtual

Initialization of the object.

Parameters

c	Vector of three or four doubles: The doubles are the parameters, a, T_3, T_1, and (optionally) T_2 of the Troe parameterization

Reimplemented from Falloff.

Definition at line 26 of file Falloff.cpp.

References Troe::m_a, Troe::m_rt1, Troe::m_rt3, Troe::m_t2, Cantera::SmallNumber, and Cantera::warn_user().

updateTemp()

void updateTemp ( doublereal  T, doublereal *  work  ) const

virtual

Update the temperature parameters in the representation.

Parameters

T	Temperature (Kelvin)
work	Vector of working space, length 1, representing the temperature-dependent part of the parameterization.

Reimplemented from Falloff.

Definition at line 60 of file Falloff.cpp.

F()

double F ( doublereal  pr, const doublereal *  work  ) const

virtual

The falloff function.

This is defined so that the rate coefficient is

\[ k = F(Pr)\frac{Pr}{1 + Pr}. \]

Here \( Pr \) is the reduced pressure, defined by

\[ Pr = \frac{k_0 [M]}{k_\infty}. \]

Parameters

pr	reduced pressure (dimensionless).
work	array of size workSize() containing cached temperature-dependent intermediate results from a prior call to updateTemp.

Returns

the value of the falloff function \( F \) defined above

Reimplemented from Falloff.

Definition at line 69 of file Falloff.cpp.

References Cantera::SmallNumber.

workSize()

virtual size_t workSize ( )

inlinevirtual

The size of the work array required.

Reimplemented from Falloff.

Definition at line 156 of file Falloff.h.

type()

virtual std::string type ( ) const

inlinevirtual

Return a string representing the type of the Falloff parameterization.

Reimplemented from Falloff.

Definition at line 160 of file Falloff.h.

getType()

virtual int getType ( ) const

inlinevirtual

Return an integer representing the type of the Falloff parameterization.

Deprecated:

To be removed after Cantera 2.5.

Reimplemented from Falloff.

Definition at line 164 of file Falloff.h.

References Cantera::warn_deprecated().

nParameters()

virtual size_t nParameters ( ) const

inlinevirtual

Returns the number of parameters used by this parameterization.

The values of these parameters can be obtained from getParameters().

Reimplemented from Falloff.

Definition at line 170 of file Falloff.h.

getParameters()

void getParameters ( double *  params ) const

virtual

Sets params to contain, in order,.

\[ (A, T_3, T_1, T_2) \]

Reimplemented from Falloff.

Definition at line 79 of file Falloff.cpp.

References Troe::m_a, Troe::m_rt1, Troe::m_rt3, and Troe::m_t2.

Member Data Documentation

m_a

doublereal m_a

protected

parameter a in the 4-parameter Troe falloff function. Dimensionless

Definition at line 179 of file Falloff.h.

Referenced by Troe::getParameters(), and Troe::init().

m_rt3

doublereal m_rt3

protected

parameter 1/T_3 in the 4-parameter Troe falloff function. [K^-1]

Definition at line 182 of file Falloff.h.

Referenced by Troe::getParameters(), and Troe::init().

m_rt1

doublereal m_rt1

protected

parameter 1/T_1 in the 4-parameter Troe falloff function. [K^-1]

Definition at line 185 of file Falloff.h.

Referenced by Troe::getParameters(), and Troe::init().

m_t2

doublereal m_t2

protected

parameter T_2 in the 4-parameter Troe falloff function. [K]

Definition at line 188 of file Falloff.h.

Referenced by Troe::getParameters(), and Troe::init().

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

• Falloff.h
• Falloff.cpp