7.2.1 Surface Coverage Reaction Rate Modification

ANSYS FLUENT has the option to modify the surface reaction rate as a function of species site coverages. In such cases, the forward rate constant for the $r$th reaction is evaluated as,

In Equation  7.2-7, the three surface coverage rate modification parameters for specie $k$ in reaction $r$ are $\eta_{k,r}$, $\mu_{k,r}$ and $\epsilon_{k,r}$. These parameters default to zero for reaction species that are not surface rate modifying. The surface (coverage) site fraction, $Z_k$ is the fraction of surface sites covered by specie $k$, and is defined as,

where $[S_k]$ is the surface site concentration and $\rho_{site}$ is the surface site density (see Equation  7.2-13).