I am trying to implement some boundary conditions in my model to simulate displacement currents "J" due to migration in an electric field. According to the literature, I have to implement the following transport of charge carriers boundary conditions ( PLEASE SEE ATTACHED SCREENSHOT) For example, for "p+", if the electric field multiplied by the normal vector is less than zero, the flux entering the solid should be zero. Otherwise, the flux should be nJ, where n is the outward normal vector from the liquid side, and J is the current flux given by upE, where u is the mobility, p is the charge density, and E is the electric field vector. I have been trying to implement this on the interface of the solid without success for at least 4 months. If anyone knows how to tackle this, it would be much appreciated
I tried to implement it using a flux boundary condition and then typing (nrEr+nzEz)(u*p)