Wall-Surface Reactions and Solid species interactions - Simulating carbon formation
 

Hi there!

I am trying to simulate carbon formation inside a porous layer during internal steam reforming of methane with fluent. I am using a heterogeneous reaction mechanism which involves an elementary surface adsorbed carbon species C(s).
Based on this species or rather on the surface coverage, I am trying to simulate formation of a carbon film layer C_film, which reduces the number of active sites.

In a next step, pyrolytic carbon C_pyr should be formed on this film carbon layer, which clogs the porous structure.

I was trying to simulate the carbon build-up similarly to the tutorial of CVD simulations. Hence, my carbon species C_film and C_pyr are modeled as solid species.
I tried to model the growth of C_pyr with a Arrhenius-type reaction between the C_film and C_pyr species. Unfortunately, the simulation shows no reaction rate and no deposition rate of C_pyr.

Does anyone know, if this modelling approach is suitable for these kind of simulations? Or should I try something completely else? Has anyone else been confronted with a similar problem?
Any hint or suggestion will be appreciated!