weirdo mole frac profile
 

I wrote this message before but somehow it's erased...

I simulate a reforming rxn (endothermic) on cylindrical tube wall and it's converged. when I check the results, I see mole/mass fractions of products increase first then start to decrease along the tube length and vice versa for the reactants. I also look at the temperature, rxn rate profiles. there is nothing seen wrong. temperature and rxn rate decreases along the tube. I simulate volume rxn, too. in this case, everything is going pretty well...

rxn:

C8H18+ 8H2O-> 8CO+ 17H2

I set H2O as site species. but also I inject steam into the reactor.

do you have any idea to solve this problem?

thanks in advance...