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Boundary Extrusion Variables

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Hello dears
I am trying to model a simple one dimensional system. I want to solve an equation of dc/dx=f (c,cp) where c is concentration in system and cp is concentration in the vicinity of boundary 2. For defining boundary condition 2, we need cp which is itself function of c at the BC.2. I have difficulty for defining BC. 2. I used PDE coefficient mode for defining governing equations and I used extrusion coupling variables in BC. 2 and destination is subdomain. The system gives error. the error is "undefined variable". I checked all constants but every thing is OK. It would be much appreciated if someone helps me.

0 Replies Last Post 2011年3月12日 GMT-5 08:41
COMSOL Moderator

Hello Saeed Shirazian

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