Cantera is a free and powerful tool in terms of solving chemical kinetics, thermodynamics, and transport processes. Although Cantera is not as fast as Chemkin whose algorithm has been optimized for commercial application, the interface provided by Cantera efficiently couples itself with user developed functions or solvers. However, the chemical mechanisms developed by well-known groups (LLNL, Milano and Nancy) are mostly in Chemkin format which is not readable for Cantera. Before using Cantera, the chemical kinetics has to be changed into Cantera format.

Cantera did release the tutorial "Working with input files" which, however, didn't give many details on how to convert mechanism format. The offical tutorail link is listed below.

http://cantera.github.io/docs/sphinx/html/matlab/input-tutorial.html

Ideally, the function ck2cti converts the kinetic and thermodynamic data of Chemkin into the Cantera format. However, an error message: "invalid literal for float(): 0.0000+03" pops up when trying to convert LLNL's gasoline mechanism. The error is due to the abnormal value format 0.0000+03 which cannot be recognized by the function. To fix this problem, please replace all 0.0000+03 to 0.00 which gives correct input format for the function.

The first type of error is essentially from kinetic file, however, thermodynamic data file also has its own problem. In the thermo file, every species contain four lines information and a number (from 1 to 4) is specified at the end of each line. For some lines, the number disappears, which leads to error 2. Add all those missing number will fix this problem.

After fixing the above problems, the cti file, which is accessible to Cantera, is generated by the function ck2cti. In order to minimize loading time, it is recommended to convert cti to xml file with importPhase command. However, this process leads to the third error, since Cantera doesn't allow zero pre-exponential factor. Cantera believes if the pre-exponential factor of a certain elementary reaction is zero, there is no need to list this elementary reaction because the rate constant is zero. Sometimes it is not possible to delete all elementary reactions with zero rate constants due to the large number involved. Instead of deleting all problematic reactions, change zero pre-exponential factor to a really small number, like o.oooo1E-99, will get rid of this error message. Since the modified number is too small to affect the overall reactivity, it is a rigorous approximation for solving problems.

The convertion was carried out in Matlab 2014a with Cantera 2.1 and Python 2.7.