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.

Reacting Flow in Porous Media

Please login with a confirmed email address before reporting spam

I am working on simulating a flow through a channel which is adjacent to a porous media which functions as an electrode to oxidize the electroactive species in the electrolyte (think fuel cell or flow battery). I have already built and successfully run a simulation of just the flow by using the Free and Porous Media Flow Physics. Now I want to essentially add a reaction in the electrode. I am trying to use the Reacting Flow in Porous Media physics, assigning porous matrix properties only to my electrode and not my channel. I have entered all the boundary conditions etc to the best of my ability, and upon running the simulation I get this error:

Failed to find a solution.
Segregated group 1

System matrix is zero.
Returned solution is not converged.

I think I may not be understanding the mass constraints COMSOL is providing, or perhaps this physics is wrong for my type of problem. Are there any tutorials available for this particular physics, as sometimes a simple example can go a long way?

1 Reply Last Post 24 lug 2013, 12:04 GMT-4

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 24 lug 2013, 12:04 GMT-4
Jacob:

Reacting flow in porous media is a combination of flow in porous medium + Dilute/Conc mass transport. So, firstly, you don't need to use a separate fluid flow module. Secondly, the reacting flow in porous media does not have equations to model electro-chemical reactions you would see in a flow battery or fuel cells. If you are looking to model chemical reactions not affected by potentials in the electrode, then you should use the reacting flow in porous media module. I would use a tertiary current distribution model if you want mass transport + electric currents in an electrode.

Sri.
Jacob: Reacting flow in porous media is a combination of flow in porous medium + Dilute/Conc mass transport. So, firstly, you don't need to use a separate fluid flow module. Secondly, the reacting flow in porous media does not have equations to model electro-chemical reactions you would see in a flow battery or fuel cells. If you are looking to model chemical reactions not affected by potentials in the electrode, then you should use the reacting flow in porous media module. I would use a tertiary current distribution model if you want mass transport + electric currents in an electrode. Sri.

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.