3.5.2 Modeling CO Electrochemistry

In practice, if carbon monoxide ( $CO$) is present in the anode fuel stream, it may be oxidized to generate carbon dioxide ( $CO_2$). This effect is modeled by introducing a $H_2$/ $CO$ split factor as follows:

where $x_{\rm H_2}$ amd $x_{\rm CO}$ are species mole fractions of $H_2$ and $CO$, respectively.

The molar source terms for each anode-side species are:

By default, Equation  3.5-9 is used to compute the $H_2$/ $CO$ split factor, however, you can define your own split factor in the user-defined function called h2_co_split_func() (see Section  4.8).