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How to import "Free and Porous Media Flow" Physics model in 1 dimension modeling

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Dear All

I am creating a one dimensional model of PEM fuel cell. I have already created 2D and 3D models on PEM fuel cells. The problem i am facing is that in 1 dimension modeling, the option of adding the physics of "Free and Porous Media flow" is not available although it was available in 2D and 3D modelling of PEM fuel cells. I need this particular physics module in order to specify the inlet velocities and the matrix properties. Although i tried to give the matrix properties through "Darcy Law" in 1D model but there is no way to input the fluid velocities.

Since I am doing a comparative study on 1D, 2D and the 3D PEM fuel cell models, I need to run them under similar conditions. Could you please suggest me a way to include that particular physics model in 1-D.

I need to input the following velocities:

Anode side (left side): 0.04 m/s (going into the anode)
Cathode side (right side): 0.006 m/s (going out of the cathode)

I am also attaching my model. I would be glad if someone can give a look to it.

Regards
Abhishek Raj


2 Replies Last Post 12 nov 2011, 01:02 GMT-5

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Posted: 1 decade ago 3 nov 2011, 04:34 GMT-4
You can apply Flux instead of Velocity, and adjust the units:

Flux (mol/m^2s) = 1/((sec/m)*(m^3/kg)*(kg/mol))
=1/( (1/ vel)*(1/density)*(molecular wt))

Regards
Naveed
You can apply Flux instead of Velocity, and adjust the units: Flux (mol/m^2s) = 1/((sec/m)*(m^3/kg)*(kg/mol)) =1/( (1/ vel)*(1/density)*(molecular wt)) Regards Naveed

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Posted: 1 decade ago 12 nov 2011, 01:02 GMT-5
Dear Naveed

Thanks a ton for your reply but I have tried that too. The thing is the simulation is showing convergence but there is no variation of current or species with voltage. I am not sure where exactly the problem is. It seems as if the desired load conditions are not getting applied properly.


Regards
Abhishek
Dear Naveed Thanks a ton for your reply but I have tried that too. The thing is the simulation is showing convergence but there is no variation of current or species with voltage. I am not sure where exactly the problem is. It seems as if the desired load conditions are not getting applied properly. Regards Abhishek

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