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.

Modules

Please login with a confirmed email address before reporting spam

Hi,

New to using COMSOL, basically I want to develop a PEMFC but do not have the batteries and fuel cell module.

Is there anyway the user can manually put in equations etc?

Also for analysis I want to be able perform cyclic voltammetry, again I see this comes standard with the batteries and fuel cell module but is there anyway around not buying the module?

Cheers,

Matthew

3 Replies Last Post Mar 8, 2017, 10:21 a.m. EST

Please login with a confirmed email address before reporting spam

Posted: 7 years ago Mar 8, 2017, 4:38 a.m. EST
Hi

I reply only to the cyclic voltammetry question:

Yes, you can do it with the Transport of Diluted Species module. Put the electrochemical reaction, R, as the flux boundary condition. Potential can be defined either as a piecewise function, but I prefer the Heaviside function in the definition of the variable E:

E = Ei + si*(v*t - 2*v*(t - ts)*flc2hs((t - ts)[1/s],0.001))
TH = exp[nF/(RT)*E]
R = n*F*k0*(CR*TH^a - CO*TH^(a-1))

where Ei is the initial potential and ts is the time of switching the direction of scan and v the scan rate; "si" is ±1, i.e. the direction of the scan; a is the charge transfer coefficient; CR and CO are the concentrations of the two species participating in the reaction and k0 the standard rate constant.

Setting up the entire battery should be possible, it just requires more work; I have not done that.

BR
Lasse
Hi I reply only to the cyclic voltammetry question: Yes, you can do it with the Transport of Diluted Species module. Put the electrochemical reaction, R, as the flux boundary condition. Potential can be defined either as a piecewise function, but I prefer the Heaviside function in the definition of the variable E: E = Ei + si*(v*t - 2*v*(t - ts)*flc2hs((t - ts)[1/s],0.001)) TH = exp[nF/(RT)*E] R = n*F*k0*(CR*TH^a - CO*TH^(a-1)) where Ei is the initial potential and ts is the time of switching the direction of scan and v the scan rate; "si" is ±1, i.e. the direction of the scan; a is the charge transfer coefficient; CR and CO are the concentrations of the two species participating in the reaction and k0 the standard rate constant. Setting up the entire battery should be possible, it just requires more work; I have not done that. BR Lasse

Please login with a confirmed email address before reporting spam

Posted: 7 years ago Mar 8, 2017, 4:41 a.m. EST
Aargh!

In the definition of R, no F, in order to have it in the dimension mol/(cm²s).

L
Aargh! In the definition of R, no F, in order to have it in the dimension mol/(cm²s). L

Please login with a confirmed email address before reporting spam

Posted: 7 years ago Mar 8, 2017, 10:21 a.m. EST
Thanks Lasse.
Thanks Lasse.

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.