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Mass absorption
Posted May 26, 2016, 12:36 p.m. EDT Chemical Reaction Engineering Version 5.1 3 Replies
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Hi everyone,
I am modelling a mass diffusion problem in tissue. I need to model absorption of a certain species by cells in the tissue. The cells can absorb a certain amount of the given species before it becomes saturated. My questions are the following:
1) How can I model mass accumulation in the cell?
2) How do I set the saturation limit of the cells?
I am new to COMSOL and would appreciate any help.
Best Regards
Aravind
I am modelling a mass diffusion problem in tissue. I need to model absorption of a certain species by cells in the tissue. The cells can absorb a certain amount of the given species before it becomes saturated. My questions are the following:
1) How can I model mass accumulation in the cell?
2) How do I set the saturation limit of the cells?
I am new to COMSOL and would appreciate any help.
Best Regards
Aravind
3 Replies Last Post May 31, 2016, 4:00 p.m. EDT
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Posted:
9 years ago
Hi
Adsorption is a tough problem. I did that 5-6 years ago but I could not find the model again, after changing an employer and desktops. But at that time I found a tutorial from this website and followed that; it was done through weak form.
Another choice is that your cells form a domain into which there is flux. Say, the concentration outside the cell domain is c1 and inside it c2. Then define flux across the boundary like this:
In the cell domain:
+kads*c1*(cmax-c2) - kdes*c2
in the exterior of cells
-kads*c1*(cmax-c2) + kdes*c2
This is Langmuir type adsorption as you certainly know.
But if it is only an adsorbed layer on the wall, you'd better resort to the weak form. It takes into account the mass balance but does not require a specific domain.
Wish you find the tutorial.
BR
Lasse
Adsorption is a tough problem. I did that 5-6 years ago but I could not find the model again, after changing an employer and desktops. But at that time I found a tutorial from this website and followed that; it was done through weak form.
Another choice is that your cells form a domain into which there is flux. Say, the concentration outside the cell domain is c1 and inside it c2. Then define flux across the boundary like this:
In the cell domain:
+kads*c1*(cmax-c2) - kdes*c2
in the exterior of cells
-kads*c1*(cmax-c2) + kdes*c2
This is Langmuir type adsorption as you certainly know.
But if it is only an adsorbed layer on the wall, you'd better resort to the weak form. It takes into account the mass balance but does not require a specific domain.
Wish you find the tutorial.
BR
Lasse
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Posted:
9 years ago
This is not the file I used as a tutorial but the best I could find easily. It has the weak form.
Lasse
Lasse
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Posted:
8 years ago
Thank you Lasse,
I appreciate the help. Will try it out.
BR
Aravind
I appreciate the help. Will try it out.
BR
Aravind