Cantera  2.3.0
SurfaceArrhenius Class Reference

An Arrhenius rate with coverage-dependent terms. More...

#include <RxnRates.h>

## Public Member Functions

SurfaceArrhenius (double A, double b, double Ta)

void addCoverageDependence (size_t k, doublereal a, doublereal m, doublereal e)
Add a coverage dependency for species k, with pre-exponential dependence a, rate constant exponential dependency m, and activation energy dependence e, where e is in Kelvin, i.e. More...

void update_C (const doublereal *theta)

doublereal updateRC (doublereal logT, doublereal recipT) const
Update the value the rate constant. More...

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

doublereal temperatureExponent () const
Return effective temperature exponent. More...

doublereal activationEnergy_R () const
Return the activation energy divided by the gas constant (i.e. More...

## Static Public Member Functions

static int type ()

## Protected Attributes

doublereal m_b

doublereal m_E

doublereal m_A

doublereal m_acov

doublereal m_ecov

doublereal m_mcov

std::vector< size_t > m_sp

std::vector< size_t > m_msp

vector_fp m_ac

vector_fp m_ec

vector_fp m_mc

## Detailed Description

An Arrhenius rate with coverage-dependent terms.

The rate expression is given by [Kee, R. J., Coltrin, M. E., & Glarborg, P. (2005). Chemically reacting flow: theory and practice. John Wiley & Sons. Eq 11.113]:

$k_f = A T^b \exp \left( \ln 10 \sum a_k \theta_k - \frac{1}{RT} \left( E_a + \sum E_k\theta_k \right) + \sum m_k \ln \theta_k \right)$

or, equivalently, and as implemented in Cantera,

$k_f = A T^b \exp \left( - \frac{E_a}{RT} \right) \prod_k 10^{a_k \theta_k} \theta_k^{m_k} \exp \left( \frac{- E_k \theta_k}{RT} \right)$

where the parameters $$(a_k, E_k, m_k)$$ describe the dependency on the surface coverage of species $$k, \theta_k$$.

Definition at line 118 of file RxnRates.h.

## Member Function Documentation

 void addCoverageDependence ( size_t k, doublereal a, doublereal m, doublereal e )

Add a coverage dependency for species k, with pre-exponential dependence a, rate constant exponential dependency m, and activation energy dependence e, where e is in Kelvin, i.e.

energy divided by the molar gas constant.

Definition at line 51 of file RxnRates.cpp.

## ◆ updateRC()

 doublereal updateRC ( doublereal logT, doublereal recipT ) const
inline

Update the value the rate constant.

This function returns the actual value of the rate constant. It can be safely called for negative values of the pre-exponential factor.

Definition at line 160 of file RxnRates.h.

## ◆ preExponentialFactor()

 doublereal preExponentialFactor ( ) const
inline

Return the pre-exponential factor A (in m, kmol, s to powers depending on the reaction order) accounting coverage dependence.

Returns reaction prexponent accounting for both a and m.

Definition at line 170 of file RxnRates.h.

## ◆ temperatureExponent()

 doublereal temperatureExponent ( ) const
inline

Return effective temperature exponent.

Definition at line 175 of file RxnRates.h.

## ◆ activationEnergy_R()

 doublereal activationEnergy_R ( ) const
inline

Return the activation energy divided by the gas constant (i.e.

the activation temperature) [K], accounting coverage dependence.

Definition at line 181 of file RxnRates.h.

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