Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
Reaction Kinetics in Hydrogen Storage system
Posted 2019年12月5日 GMT-5 05:59 Heat Transfer & Phase Change, Computational Fluid Dynamics (CFD), Chemical Reaction Engineering Version 5.4 0 Replies
Please login with a confirmed email address before reporting spam
The below post is related to an archived discussion
Hello Guys, I am new to COMSOL . I needed to include a "mass source" in Darcy law model and "heat source" in heat transfer in porous media model.The source term is as follows Mass source formula: -(1-porosity)*m
where, porosity=0.5, Kinetics Equation: m=Caexp(-Ea/(RuT))log(P/Peq)(rho_ss-rho_s) rho_ss=3240kg/m^3, rho_s=3200kg/m^3, Ca=100(1/s), Ru=8.314(J/kg.K), Ea=3e5(J/kg). Heat source formula: (1-porosity)dHm where, dH=30800 J/mol
Peq is found by van't Hoff equation, Peq=exp(A-B/T) where A and B are material constants, T is domain temperature and P is gas pressure. The problem that i have is (i) when i try to include "Peq" and "m" formulae in global definitions>variables, i get error message in exp and log functions. when i remove exp and log functions from the respective equations, no error message is displayed. I don't know what to do. Is it because P and T (the unknowns) should be given some arbitrary value initially or should i do something else? Your suggestions will be greatly helpful.Thank you.
Hello Adeleke Adetayo
Your Discussion has gone 30 days without a reply. If you still need help with COMSOL and have an on-subscription license, please visit our Support Center for help.
If you do not hold an on-subscription license, you may find an answer in another Discussion or in the Knowledge Base.