KUCRS-Manual

ex-1: n-hexane(SMILES)

! n-hexane
fuel{ 'n' CCCCCC }

ex-2: 1-pentene(SMILES)

! 1-pentene
fuel{ C=CCCC }

ex-3: iso-octane(SMILES)

! iso-octane =
! 2,2,4-trimethylpentane
fuel{'i'CC(C)(C)CC(C)C}

ex-4: iso-butanol(SMILES)

! iso-butanol
fuel{ 'i'
 CC(C)CO
}

ex-5: 4-isopropylheptane(SMILES)

fuel{CCCC(C(C)C)CCC}

ex-6: 4-isopropylheptane(trad.)

alkane{
 heptane(4-et(1-me))
}

ex-7: ethane/n-butane mixture

alkane{ ethane }
fuel{ CCCC }

ex-8: methylcyclohexane(SMILES)

fuel{'c'C1(C)CCCCC1}

ex-9: methylcyclohexane(trad.)

alkane{[c]c-hexane(1-me)}

Fuel Input

The current version of the KUCRS combust program (the first program executed by run_comb) accepts (1) any non-cyclic alkanes, (2) single-ring (5- to 7-membered) cyclic alkanes, (3) any non-cyclic alkenes (mono-ens), and (4) any non-cyclic alcohols as fuel molecules. Several examples are shown in the right table. In addition to the traditional input which allows to specify only alkanes, from Rev. 2010.02.21, KUCRS also accepts SMILES specification of fuel molecules. Both input styles may be mixed in the mutiple full specification.

SMILES input

The rule set for the fuel alkane specifications by SMILES are as follows:

A fuel-specification should begin with 'fuel{' and end by '}'.
The mixture of more than two fuels can be specified by sequential fuel-specifications.
A string enclose in the single quotations (') may be placed just after 'fuel{' to specify the prefix of the fuel name. For example, n-hexane specified in the ex-1 to the right will be given a name 'nC6H14' while it will be named 'C6H14' without the specification of 'n'.
Specify the structure of the compound by SMILES.

Traditional input

The traditional rule set for the fuel alkane specifications are as follows:

An alkane-specification should begin with 'alkane{' and end by '}'.
The mixture of more than two alkanes can be specified by sequential alkane-specifications.
A string enclose in the brackets ('[ ]') may be placed just after 'alkane{' to specify the prefix of the fuel name. For example, methycyclohexane specified in ex-9 to the right will be given a name 'cC7H14' while it will be named 'C7H14' without the specification of '[c]'.
An alkane is designated by main_chain (position-substituent)(..-..)... The substitution can be specified recursively, as shown in the ex-6 of 4-isopropylheptane.
The 'main_chain' may be one of 'c-pentane', 'c-hexane', or 'c-heptane' which disignate cyclic alkanes. (The supported number of members in the ring is 5 to 7.)
One may place any number of line-breaks and space characters in any place of the inputs.
The part beginning with '!' to the line end is regarded as comment and is ignored.

Customizing KUCRS

Though limited in the beta binary release, some of the autogeneration rules can be customized by the user. The customizable part can be found in the set of the text files in the libdata directory (or folder) in the KUCRS directory.

Base Mechanism

The base kinetic mechanism for low-carbon number species is contained in the following three files in libdata directory.

bas_spcs.inp (elements & species blocks in Chemkin format)
bas_thrm.dat (thermo block)
bas_rxns.inp (reactions block)
bas_tran.inp (transport data)

The base mechanism can be edited, if necessary, without disturbing the behavior of KUCRS when the species block is unchanged. You would need to edit the KUCRS internal data file mol_main.dat consistently when you are to add, delete, or rename species.

Reaction Rate Macro

Reaction type specific rate parameters are stored in the KUCRS with type-specific macros (names). For example, Habs/by-H/Prim is the rate parameters for hydrogen abstraction reaction from a primary site of a hydrocarbon by an H atom. The macros and the corresponding rate parameters are read from the file rxn_macr.dat. The rate parameters written in this file can be edited safely. However, adding new type of reaction is impossible in the current version of KUCRS. (It requires the change of the source code.)

Thermodata

Tables of the thermodata can be found in libdata/GROUPS directory. They are in the format of THERM program. Revising the thermodata for the existing groups can be done by editing the values in these files. Defining new groups or changing the group definition can be also done by editing these files with the KUCRS group definition files, grp_main.dat, grp_cyc.dat, and grp_rad.dat consistently.