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Hi everybody,

I am stuck with the following problem about how setting boundary conditions:

I have a simple geometry: actually 2D, but for what matters here, one may consider a simple 1D, with 0 < x < 1.

Mine is a PDE problem in coefficient forms: a total of 7 equations, 3 of them second-order, the other 4 first-order.
Thus, I have to set a total of 10 boundary conditions.
Let us call brad, bpol, btor, vrad, vpol, vtor, pot, the 7 independent variables.

My problem is this:
Out of the 10 BC's, I have to impose 9 of them on the left side: some of the are the values of the independent
variables (thus a Dirichlet BC), others are their derivatives.
In detail, I have to impose on the left side (x = 0):
brad, bpol, btor, vrad, vtor, vpol AND
vrad_x, vpol_x, vtor_x (the values of the derivatives)

Finally, I have just one BC on the right side: pot

Comsol allows me to set up to 7 constraints for each side. How can I override this limit ?


Thanks for your assistance

Fabio