rwest
commented
1 year ago Here's the entry in RMG-database: https://github.com/ReactionMechanismGenerator/RMG-database/blob/0de0ae134683ba83d89b06b22879e5f0cb41ef3a/input/kinetics/libraries/NOx2018/reactions.py#L8496
entry(
index = 467,
label = "HCCO + OH <=> CO2 + CH2",
degeneracy = 1,
duplicate = True,
kinetics = MultiPDepArrhenius(
arrhenius = [
PDepArrhenius(
pressures = ([0.1, 1, 10], 'atm'),
arrhenius = [
Arrhenius(
A = (1.7e+15, 'cm^3/(mol*s)'),
n = -1.19,
Ea = (-521, 'cal/mol'),
T0 = (1, 'K'),
),
Arrhenius(
A = (7.2e+27, 'cm^3/(mol*s)'),
n = -5.023,
Ea = (2468, 'cal/mol'),
T0 = (1, 'K'),
),
Arrhenius(
A = (1e+91, 'cm^3/(mol*s)'),
n = -20.137,
Ea = (114841, 'cal/mol'),
T0 = (1, 'K'),
),
],
),
PDepArrhenius(
pressures = ([0.1, 1, 10], 'atm'),
arrhenius = [
Arrhenius(
A = (-7.4e+17, 'cm^3/(mol*s)'),
n = -1.92,
Ea = (1686, 'cal/mol'),
T0 = (1, 'K'),
),
Arrhenius(
A = (1.1e+21, 'cm^3/(mol*s)'),
n = -2.28,
Ea = (16960, 'cal/mol'),
T0 = (1, 'K'),
),
Arrhenius(
A = (2.3e+65, 'cm^3/(mol*s)'),
n = -16.078,
Ea = (19592, 'cal/mol'),
T0 = (1, 'K'),
),
],
),
PDepArrhenius(
pressures = ([0.01, 0.1, 1, 10], 'atm'),
arrhenius = [
Arrhenius(A=(1e+19, 'cm^3/(mol*s)'), n=-2.08, Ea=(44, 'cal/mol'), T0=(1, 'K')),
Arrhenius(A=(1.4e+19, 'cm^3/(mol*s)'), n=-2.12, Ea=(88, 'cal/mol'), T0=(1, 'K')),
Arrhenius(A=(7.1e+19, 'cm^3/(mol*s)'), n=-2.3, Ea=(824, 'cal/mol'), T0=(1, 'K')),
Arrhenius(
A = (1.8e+20, 'cm^3/(mol*s)'),
n = -2.34,
Ea = (2421, 'cal/mol'),
T0 = (1, 'K'),
),
],
),
],
),
)and here is the extract from the original CHEMKIN file from https://doi.org/10.1016/j.pecs.2018.01.002
HCCO+OH=CO2+CH2 7.2E27 -5.023 2468 ! 1 atm
!PLOG / 0.01 3.4E14 -1.400 1240 / !results in negative rate constant
PLOG / 0.1 1.7E15 -1.190 -521 /
!PLOG / 1 9.3E15 -0.970 -309 / !replaced convergence trouble
PLOG/ 1.00 7.2E27 -5.023 2468 / !refit
PLOG/ 10.00 1.0E91 -20.137 114841 / !refit
!PLOG / 10 6.0E15 -0.640 363 /
!PLOG / 100 1.0E14 0.060 447 / !results in negative rate constant
DUPLICATE
HCCO+OH=CO2+CH2 1.1E21 -2.280 16960 ! 1 atm
!PLOG / 0.01 -3.3E17 -2.220 3684 /
PLOG / 0.1 -7.4E17 -1.920 1686 /
!PLOG / 1 -5.3E18 -1.740 2024 /
PLOG/ 1.00 1.1E21 -2.280 16960 / !Average (max) fitting error: 0.6% (3.2%) over T of 400--3000 [K]
PLOG/ 10.00 2.3E65 -16.078 19592 /
!PLOG / 10 -2.6E19 -1.640 3539 /
!PLOG / 100 -5.6E19 -1.510 5657 /
DUPLICATE
! Xiong et al., Combust. Flame 161 (2014) 885�897
! ASSUMING 3-CHCOOH = 1-CHCOOH ==fast==> CO2+CH2
DUPLICATE
HCCO+OH=CO2+CH2 7.1E19 -2.300 824 ! 1 atm
PLOG / 0.01 1.0E19 -2.080 44 /
PLOG / 0.1 1.4E19 -2.120 88 /
PLOG / 1 7.1E19 -2.300 824 /
PLOG / 10 1.8E20 -2.340 2421 /
!PLOG / 100 8.2E02 2.870 -3 / !results in negative rate constant
!PLOG / 100 -2.3E24 -2.700 20416 /
! Xiong et al., Combust. Flame 161 (2014) 885�897
! ASSUMING 3-CHCOOH = 1-CHCOOH ==fast==> CO2+CH2
DUPLICATEAs you can see, the chemkin file is a bit of a confusing mess with many lines commented out. But it also uses three duplicate reactions (although that is not needed for PLOG format).
So it's not clear yet what error, if any, RMG has made. If you can figure out that there is one, and what it is, please do elucidate here!
It's quite possible that there is, because this type of thing is complicated (see https://github.com/ReactionMechanismGenerator/RMG-Py/pull/1341 for example)
While modeling my combustion, I found there is one reaction in my kinetic library of the multiple Arrhenius type: HCCO + OH <=> CO2 + CH2 which uses the sum of multiple k's as the rate constant
RMG handled this incorrectly and split it into three duplicate reactions:
Apparently this has caused some trouble in my model as it has some very large values (1.000e+91, 2.300e+65). I have to delete them to avoid errors in my other tool, i.e., Cantera