rmgpy.kinetics.ThirdBody¶

class
rmgpy.kinetics.
ThirdBody
(arrheniusLow=None, Tmin=None, Tmax=None, Pmin=None, Pmax=None, efficiencies=None, comment='')¶ A kinetic model of a phenomenological rate coefficient \(k(T, P)\) using thirdbody kinetics. The attributes are:
Attribute Description arrheniusLow The Arrhenius kinetics at the lowpressure limit Tmin The minimum temperature at which the model is valid, or zero if unknown or undefined Tmax The maximum temperature at which the model is valid, or zero if unknown or undefined Pmin The minimum pressure at which the model is valid, or zero if unknown or undefined Pmax The maximum pressure at which the model is valid, or zero if unknown or undefined efficiencies A dict associating chemical species with associated efficiencies comment Information about the model (e.g. its source) Thirdbody kinetics simply introduce an inert third body to the rate expression:
\[k(T,P) = k_0(T) [\mathrm{M}]\]Above, \([\mathrm{M}] \approx P/RT\) is the concentration of the bath gas. This formulation is equivalent to stating that the kinetics are always in the lowpressure limit.

Pmax
¶ The maximum pressure at which the model is valid, or
None
if not defined.

Pmin
¶ The minimum pressure at which the model is valid, or
None
if not defined.

Tmax
¶ The maximum temperature at which the model is valid, or
None
if not defined.

Tmin
¶ The minimum temperature at which the model is valid, or
None
if not defined.

arrheniusLow
¶ arrheniusLow – rmgpy.kinetics.arrhenius.Arrhenius

changeRate
(self, double factor)¶ Changes kinetics rate by a multiple
factor
.

comment
¶ comment – str

discrepancy
(self, KineticsModel otherKinetics) → double¶ Returns some measure of the discrepancy based on two different reaction models.

efficiencies
¶ efficiencies – dict

getCanteraEfficiencies
(self, speciesList)¶ Returns a dictionary containing the collider efficiencies for this PDepKineticsModel object suitable for setting the efficiencies in the following cantera reaction objects: ThreeBodyReaction, FalloffReaction,`ChemicallyActivatedReaction`

getEffectiveColliderEfficiencies
(self, list species) → ndarray¶ Return the effective collider efficiencies for all species in the form of a numpy array. This function helps assist rapid effective pressure calculations in the solver.

getEffectivePressure
(self, double P, list species, ndarray fractions) → double¶ Return the effective pressure in Pa for a system at a given pressure P in Pa composed of the given list of species (Species or Molecule objects) with the given fractions.

getRateCoefficient
(self, double T, double P=0.0) → double¶ Return the value of the rate coefficient \(k(T)\) in units of m^3, mol, and s at the specified temperature T in K and pressure P in Pa. If you wish to consider collision efficiencies, then you should first use
getEffectivePressure()
to compute the effective pressure, and pass that value as the pressure to this method.

highPlimit
¶ highPlimit – rmgpy.kinetics.model.KineticsModel

isIdenticalTo
(self, KineticsModel otherKinetics) → bool¶ Checks to see if kinetics matches that of other kinetics and returns
True
if coeffs, kunits, Tmin,

isPressureDependent
(self) → bool¶ Return
True
since all objects derived from PDepKineticsModel represent pressuredependent kinetics.

isPressureValid
(self, double P) → bool¶ Return
True
if the pressure P in Pa is within the valid pressure range of the kinetic data, orFalse
if not. If the minimum and maximum pressure are not defined,True
is returned.

isSimilarTo
(self, KineticsModel otherKinetics) → bool¶ Returns
True
if rates of reaction at temperatures 500,1000,1500,2000 K and 1 and 10 bar are within +/ .5 for log(k), in other words, within a factor of 3.

isTemperatureValid
(self, double T) → bool¶ Return
True
if the temperature T in K is within the valid temperature range of the kinetic data, orFalse
if not. If the minimum and maximum temperature are not defined,True
is returned.

setCanteraKinetics
(self, ctReaction, speciesList)¶ Sets the kinetics and efficiencies for a cantera ThreeBodyReaction object

toHTML
(self)¶ Return an HTML rendering.
