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Coupling transport of a species to surface reactions

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Hello,

I am trying to make a model that has laminar flow, transport of a dilute species, and surface reactions. I want the laminar flow and transport of a dilute species to distribute the chemical species throughout the model, and then for there to be reactions that consume that species on the surface of a sphere. I am having a very hard time trying to couple the species that is in the transport of dilute species to the species that is being consumed in the surface reactions. Is there any way to do this? Or should I just try to add the consumption of the species in the transport, which I could do, but I could not have the reactions occur only of the surface of a sphere.
Essentially I want there to be chemical reaction on the surface of a sphere, but I need those reactions to alter the space around it. I need the chemical species to decrease its concentration as it gets closer to the sphere.
Any help would be much appreciated.
Thank you!

Kelley

6 Replies Last Post Nov 11, 2016, 4:40 p.m. EST

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Posted: 1 decade ago Jul 6, 2012, 9:29 p.m. EDT
Hi,
Could u explain it properly, wht kind of reactions are u trying solve, and u can also put few pics of your model, if u don't want to share ur model in explaining it.
Hi, Could u explain it properly, wht kind of reactions are u trying solve, and u can also put few pics of your model, if u don't want to share ur model in explaining it.

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Posted: 8 years ago May 20, 2016, 2:18 p.m. EDT
Hello Kelley,

I am relatively new to COMSOL and am running a very similar simulation and having the same difficulty you mentioned in your post. Did you ever get this issue solved? If so I'd love to have some guidance on how I might be able to correct my simulation.

Hello Kelley, I am relatively new to COMSOL and am running a very similar simulation and having the same difficulty you mentioned in your post. Did you ever get this issue solved? If so I'd love to have some guidance on how I might be able to correct my simulation.

Walter Frei COMSOL Employee

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Posted: 8 years ago May 20, 2016, 3:08 p.m. EDT
Dear Kelly, Joshua,

What you are describing can be done with the Chemical Reaction Engineering Module.
Please see, for example:
www.comsol.com/model/protein-adsorption-1397

And, for a basic introductory example which shows how to manually enter governing equations if you do not have the Chemical Reaction Engineering Module, see:
www.comsol.com/model/transport-and-adsorption-5

Best Regards,
Dear Kelly, Joshua, What you are describing can be done with the Chemical Reaction Engineering Module. Please see, for example: https://www.comsol.com/model/protein-adsorption-1397 And, for a basic introductory example which shows how to manually enter governing equations if you do not have the Chemical Reaction Engineering Module, see: https://www.comsol.com/model/transport-and-adsorption-5 Best Regards,

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Posted: 8 years ago May 20, 2016, 3:29 p.m. EDT
Walter,

I appreciate the help but unfortunately I am unable to open your models as I am running 4.3a. Do you have any models that would run on that version?

The simulation I am running is a fluid flow running through a cylindrical chamber from an inlet, hitting a sphere, going around the sphere, then leaving through an outlet. I am running a time-dependent study with the physics laminar flow and transport of diluted species. Currently, I have species A coming in as an inflow and I would like the local concentration of species A on the surface of the sphere (inside the cylindrical channel) to determine how much of Species B is released from the sphere.

Is there a way I can simulate this if I only have the Microfluidics Module purchased?

Thanks again,

Josh
Walter, I appreciate the help but unfortunately I am unable to open your models as I am running 4.3a. Do you have any models that would run on that version? The simulation I am running is a fluid flow running through a cylindrical chamber from an inlet, hitting a sphere, going around the sphere, then leaving through an outlet. I am running a time-dependent study with the physics laminar flow and transport of diluted species. Currently, I have species A coming in as an inflow and I would like the local concentration of species A on the surface of the sphere (inside the cylindrical channel) to determine how much of Species B is released from the sphere. Is there a way I can simulate this if I only have the Microfluidics Module purchased? Thanks again, Josh

Walter Frei COMSOL Employee

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Posted: 8 years ago May 20, 2016, 5:31 p.m. EDT
Dear Josh,

We do of course encourage you to come back on subscription, and to upgrade to one of the Modules that support surface reactions. See www.comsol.com/products/specifications/chemical/ for a listing of what features are available in which Modules.

Also, take a look over the step-by-step instructions in the second example (www.comsol.com/model/transport-and-adsorption-5) you should be able to reproduce these in any recent version of the software.

Best Regards,
Dear Josh, We do of course encourage you to come back on subscription, and to upgrade to one of the Modules that support surface reactions. See https://www.comsol.com/products/specifications/chemical/ for a listing of what features are available in which Modules. Also, take a look over the step-by-step instructions in the second example (https://www.comsol.com/model/transport-and-adsorption-5) you should be able to reproduce these in any recent version of the software. Best Regards,

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Posted: 8 years ago Nov 11, 2016, 4:40 p.m. EST
Hi Walter,
In the "www.comsol.com/model/transport-and-adsorption-5" model you suggested, the chemical reaction is on a one-dimensional surface. If the surface is a sphere (3D), how would you formulate the PDE? Will that be similar to the model?
Thank you in advance.
Hi Walter, In the "https://www.comsol.com/model/transport-and-adsorption-5" model you suggested, the chemical reaction is on a one-dimensional surface. If the surface is a sphere (3D), how would you formulate the PDE? Will that be similar to the model? Thank you in advance.

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