Hi Yang
sub: electrode boundary condition
My problem is a pressure driven flow inside a microchannel, that generates ionic current due to
electric double layer formation. there is no external electric field. I solve Poisson Nernst Planck equations along with Navier Stokes, in my case ionic current is (velocity)w*(np-nn) (net charge density),
What I want to model is the "streaming current measurement, no potential exists in streaming current mode due to electrodes", when in practice we put two electrodes at the ends of channel....how can I change the streaming potential modeling to streaming current modeling? I need an electrode boundary condition at exit ? thats my problem now, can you help?
thank you
Abraham
QUOTE]
If a boundary condition contains a pde you have to use weak form to get correct results, i.e. you have to solve the Laplace equation with the continuity PDE relating the derivative of the potential on the edge of the double layer using the weak form mode. Therefore, you can not solve this problem using the conductive dc media mode.
The Comsol Modeling guide has a chapter , page 345 in my version, on how to convert to weak form.
Regards,
Dr Neophytos Loucaides
Hi Dr Loucaides,
You are the best person to address my question, as the paper i am following is written by you :)
Thank you for you tip, i am now studying the weak form chapter.
Just a quick check, is it possible to use a weak constraints in the existing conductive DC media mode rather then converting all to weak form mode?
I hope to communicate with you further on this topic.
With Best Regards,
yang
sub: electrode boundary condition
My problem is a pressure driven flow inside a microchannel, that generates ionic current due to
electric double layer formation. there is no external electric field. I solve Poisson Nernst Planck equations along with Navier Stokes, in my case ionic current is (velocity)w*(np-nn) (net charge density),
What I want to model is the "streaming current measurement, no potential exists in streaming current mode due to electrodes", when in practice we put two electrodes at the ends of channel....how can I change the streaming potential modeling to streaming current modeling? I need an electrode boundary condition at exit ? thats my problem now, can you help?
thank you
Abraham
QUOTE]
If a boundary condition contains a pde you have to use weak form to get correct results, i.e. you have to solve the Laplace equation with the continuity PDE relating the derivative of the potential on the edge of the double layer using the weak form mode. Therefore, you can not solve this problem using the conductive dc media mode.
The Comsol Modeling guide has a chapter , page 345 in my version, on how to convert to weak form.
Regards,
Dr Neophytos Loucaides
Hi Dr Loucaides,
You are the best person to address my question, as the paper i am following is written by you :)
Thank you for you tip, i am now studying the weak form chapter.
Just a quick check, is it possible to use a weak constraints in the existing conductive DC media mode rather then converting all to weak form mode?
I hope to communicate with you further on this topic.
With Best Regards,
yang
