### 9.1.1. Naming Convention for Reaction Schemes

For the predefined reaction schemes provided in the `REACTIONS` library, the following conventions apply:

- Reactions with `WD` n in the name correspond to the appropriate Westbrook and Dryer [66] reaction scheme with n number of steps. Note that this publication contains misprints for certain reaction rates [220], which have been confirmed by the authors of the original paper. We are using the corrected coefficients provided by Westbrook and Dryer in their response to Coffee’s comment, which is included at the end of [220].

- Reactions with `WGS` in the name correspond to reactions with the Water Gas Shift forward/backward reaction:

  | (9–1)

- Reactions with `NO PDF` in the name are schemes that include the NO formation model. For details, see NO Model. The reaction rates for NO formation account for turbulent fluctuations of temperature.

- It is recommended that you do not use reactions with just `NO` in the name, as these schemes do not account for temperature fluctuations when computing reaction rates of NO, and are therefore less accurate.

For the `WD` n reactions, single reaction step schemes can still be described as multi-step when the purpose of the additional step is to add an additional passive component (N2) to a single step reaction. The reaction step itself remains single step in these cases.

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