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Error - Failed to evaluate variable jacobian

Posted Mar 30, 2013, 5:04 p.m. EDT Fluid & Heat, Microfluidics, Battery Design, Studies & Solvers Version 4.3a 1 Reply

Paytong Goodrich

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Hello,

I am currently working with the batteries and fuel cells module and I am attempting to create a model of a micro-scale PEM fuel cell. Right now I am starting by just trying to solve a free and porous media flow physics to begin with, but I am getting an error that says:
"Failed to evaluate variable Jacobian
-Variable : U_in_Anode
-Geometry: 1
-Boundary: 5"

Block 5 is the anode chamber of the cell, and U_in_Anode is the volumetric flow rate of the anolyte. What is likely to be the error in this, and how can a fix it?

Thank you in advance.

1 Reply Last Post Mar 30, 2013, 5:19 p.m. EDT

Paytong Goodrich

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Posted: 1 decade ago

I forgot to note, this fuel cell does not use gas diffusion electrodes. It is a microbial fuel cell, so all fluids run through it are in a liquid state. I will be approximating values for current production later, right now I just need to find out how the fluid flows through the cell chambers and electrodes.

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Error - Failed to evaluate variable jacobian

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