Menu

Discussion Forum

New Discussion
Filter

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

No-homogeneous initial condition

Posted Dec 3, 2014, 10:26 p.m. EST Chemical Reaction Engineering Version 5.0 6 Replies

Ximena Paz Barrios Pizarro
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hello
I am trying to build a mass transport model that has a higher solute concentration in a region than in other of the same domain.
Is this possible in COMSOL? How?
6 Replies Last Post Dec 12, 2014, 8:25 a.m. EST
Lasse Murtomäki
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago Dec 4, 2014, 4:47 a.m. EST
Hi

It is possible. Either you use a function to define an initial distribution or split your domain into smaller ones having varying initial concentrations. No boundary conditions are needed at the internal boundaries.

br
Lasse
Hi It is possible. Either you use a function to define an initial distribution or split your domain into smaller ones having varying initial concentrations. No boundary conditions are needed at the internal boundaries. br Lasse
Ximena Paz Barrios Pizarro
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago Dec 4, 2014, 12:08 p.m. EST
Hi

And how can I do that?
I am a new COMSOL user, so I will be very thankful if you told me how to do that.

Hi And how can I do that? I am a new COMSOL user, so I will be very thankful if you told me how to do that.
Lasse Murtomäki
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago Dec 5, 2014, 4:38 a.m. EST
Please tell me what you wish to do. I can try.
Please tell me what you wish to do. I can try.
Ximena Paz Barrios Pizarro
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago Dec 6, 2014, 12:54 p.m. EST
Hello

My system consists in a membrane that is charged with a solute, but it is not homogeneous. The solute concentration is higher near to the surface than inside the membrane.
So, I built a 1D model and I want changes in concentration along the interval. Maybe, a linear way could be useful.

Thank you!
Hello My system consists in a membrane that is charged with a solute, but it is not homogeneous. The solute concentration is higher near to the surface than inside the membrane. So, I built a 1D model and I want changes in concentration along the interval. Maybe, a linear way could be useful. Thank you!
Lasse Murtomäki
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago Dec 8, 2014, 4:34 a.m. EST
Hi

Let's say that you membrane has a thickness H and the maximum concentration in the membrane is Cmax, and minimum concentration is Cmin. If you wish, e.g. a parabolic distribution in the membrane, make an initial concentration

4*(Cmax-Cmin)*(x/H)*(x/H - 1) + Cmax

which is Cmin at x = H/2 and Cmax at x = 0 and x = H

Or whatever you wish to depict your initial distribution.

br
Lasse
Hi Let's say that you membrane has a thickness H and the maximum concentration in the membrane is Cmax, and minimum concentration is Cmin. If you wish, e.g. a parabolic distribution in the membrane, make an initial concentration 4*(Cmax-Cmin)*(x/H)*(x/H - 1) + Cmax which is Cmin at x = H/2 and Cmax at x = 0 and x = H Or whatever you wish to depict your initial distribution. br Lasse
Ximena Paz Barrios Pizarro
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago Dec 12, 2014, 8:25 a.m. EST
Thank you!

It works perfectly! :)
Thank you! It works perfectly! :)

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content