[Fluent Inc. Logo] return to home search
next up previous contents index

14.2.6 Importing a Surface Kinetic Mechanism in CHEMKIN Format

Importing surface kinetic mechanisms in CHEMKIN format (Section  14.1.9) requires that the gas phase mechanism file accompany the surface mechanism file for full compatibility with CHEMKIN. If the gas phase mechanism file is not available, then you will need to create one that you will import along with the surface mechanism file. The mechanism files are imported into FLUENT using the CHEMKIN Mechanism Import panel (Figure  14.2.1).

File $\rightarrow$ Import $\rightarrow$ CHEMKIN Mechanism...

Figure 14.2.1: The CHEMKIN Mechanism Import Panel for Surface Kinetics
figure

In the CHEMKIN Mechanism Import panel

1.   Enter a name for the chemical mechanism under Material Name.

2.   Enable Import Surface CHEMKIN Mechanism.

3.   Enter the path to the Gas Phase CHEMKIN Mechanism File (e.g., path/ gas-file.che) and the Surface CHEMKIN Mechanism File (e.g., path/ surface-file.che).

4.   Specify the location of the Thermodynamic Data File ( thermo.db). The format for thermo.db is detailed in the CHEMKIN User's Guide [ 178]. The default thermo.db file supplied with FLUENT has only gas phase species available. You will need to supply a surface thermo.db file for your surface species if this thermo information is not in the mechanism file.

figure   

Note that FLUENT will initially search for the thermodynamic data in the Surface CHEMKIN Mechanism File. If the data does not exist in the mechanism file, then FLUENT will search for the thermodynamic data in the specified Thermodynamic Database File.

5.   (Optional). Import transport properties by enabling the Import Transport Property Database and entering the path to that file.

To read in KINetics transport properties, go to Section  14.1.9 for detailed information.

6.   Click the Import button.

FLUENT will create a material with the specified name, which will contain the CHEMKIN data for the species and reactions, and add it to the list of Fluent Mixture Materials. You can view all of the reactions by clicking on the Edit... button to the right of Mechanism, under Properties in the Materials panel.

Note that for surface reaction mechanisms, the surface reaction rate constant can be expressed in terms of a sticking coefficient. FLUENT will convert this sticking coefficient form to the Arrhenius rate expression [ 177].

figure   

The CHEMKIN import facility does not provide full compatibility with all CHEMKIN rate formulations. To access more complete functionality, you should consider the KINetics module option described in Section  14.1.3.



Compatibility and Limitations for Gas Phase Reactions


FLUENT will allow for the following reaction types:

FLUENT will not allow for the following reaction types:

figure   

Note that the reaction types that FLUENT will not allow are mostly applicable to plasmas.



Compatibility and Limitations for Surface Reactions


FLUENT will allow for the following reaction types:

FLUENT will not allow for the following reaction types:

figure   

FLUENT will warn you of any incompatibilities.

For a detailed description of the keywords, see [ 177].


next up previous contents index Previous: 14.2.5 Postprocessing for Surface
Up: 14.2 Wall Surface Reactions
Next: 14.3 Particle Surface Reactions
© Fluent Inc. 2006-09-20