3D Transport and Adsorption model on Comsol

AI Thread Summary
The discussion focuses on a user attempting to create a 3D transport and adsorption model in Comsol Multiphysics, specifically dealing with the adsorption of a species to a surface in a microfluidic cell. The user experiences logical values for concentration when certain simulation settings are disabled, but encounters nonsensical results when all settings are enabled, particularly a decrease in concentration at one probe after 35 seconds. Despite trying different meshes and solvers, the user remains stuck on this issue for two months. Suggestions from other users include comparing the model to reference examples, but the original poster has already done this without success. The thread highlights the challenges of modeling complex interactions in fluid dynamics and adsorption processes.
El Pachon
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Hi everyone,

I'm trying to design a simple model by using Comsol Multiphysics. I set an inlet concentration of a species "cp" that will be adsorbed to a circular surface located at the center of the microfluidic cell (I named the concentration of adsorbed protein "cpl" ). I used laminar flow, transport of diluted species and surface reaction nodes.

When I run the simulation with the Surface Reaction node and the Flux section of the Transport of Diluted Species disabled, I get logical values for cp. When I run the simulation with all the sections enabled, the concentrations of cp at the 5 probes I created no longer make much sense and I get a decrease of the cp concentration on the left probe ( red line in Proble Plot 3) at, approximately, 35 seconds of simulation. This will obviously affect my cpl concentration (Probe Plot 8).

I've tried different meshes and different solvers and I have no idea why this is happening, have been stuck with this problem for two months now so any help would be greatly appreciated.

P.S.: It won't let me attach the file so I posted the link to where it is, if that's not ok I'll delete it. http://www.comsol.com/community/forums/general/thread/33120/

Thanks in advance.
 
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Hi Niklas,

Thank you very much for your suggestion.
I've done that already, I've also compared my model with another one called transport and adsorption, which is a similar model in 2D but I've had no success.

Would you have any other suggestions?
Thank you in advance.
 
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