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Simple two domain reaction diffusion problem with common interface

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Hi - This is a simple problem where one species is in an inner domain diffusing out into another domain. However reaction happens outside the first domain only. My approach was to create domains (as an assembly) and define the reaction diffusion equations for them separately. Then connect the physics through an identity pair where the concentration in the outer boundary of the first domain is equal to the concentration of the inner boundary of the outer domain. When I run it, i get a message : "failed to evaluate variable" and i don't know what is the source of this issue. Could anyone help me out. I have attached the comsol file with the model. Thanks!

P.S - I was curious about the other approach where I define a weak pde interface.


2 Replies Last Post 06.07.2011, 21:15 GMT-4
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Hello Melissa Rice

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Posted: 1 decade ago 09.03.2011, 16:46 GMT-5
This is how you should solve the problem..see the attached file
This is how you should solve the problem..see the attached file


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Posted: 1 decade ago 06.07.2011, 21:15 GMT-4
These files seem corrupted... Will they open with 3.5a? Are they viruses??
These files seem corrupted... Will they open with 3.5a? Are they viruses??

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