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Use of dependent variables and their derivatives in a custom equation

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Hello,

I have a system that uses two EC physics modules. Dependent variables of the two EC modules are "Vint" and "V". Inside one EC module I have a 'Normal Current Density' boundary condition where the equation is, -n.J = J_n. For J_n I want to use the variable "i", where,
i = i1 + i2 ;
i1 = Vint - V ;
i2 = Vint' - V' ; where Vint' and V' are first order time derivatives of the dependent variables Vint and V respectively.

How do I use these equations and set J_n for the 'Normal Current Density' boundary condition.

0 Replies Last Post Aug 13, 2015, 2:00 p.m. EDT
COMSOL Moderator

Hello Saliya Kumara

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