[Getdp] Re: Difficult BC -> sth arranged

[Nacho Andres de la Fuente]

Hi All,

More or less I realized that by using $XS, $YS and $ZS .. I obtain the
values of the source coordinates .. would they be those associated with
the nodes?
Would this be right:?
/* Exterior Plasma */
Function {
        here it goes the definition of constants ..
        Colat = Atan2[Sqrt[$XS*$XS+$YS*$YS],$ZS];
        PhotoFunc = Exp[$Potential]*some_func1($Colat);
        ColltdPlasma = some_func2($Colat);
}

/* BOUNDARY CONDITIONS Definition            */
/* Photoelectric Emission Boundary Condition */
Constraint {
        {Name PhotoElectric;
         Case {Region SurfextIll; Value 1.; PhotoFunc[] }
}
/* Dark Side */
Constraint {
        {Name EnvPlasma; Type Assign;
         Case {Region SurfextDark; Value 1.; ColltdPlasma[]  }
}

Thanks for the time you are spending on us newbies .. you are earning
heaven for a free work :-)

Best Regards,
Nacho

> Ok, now you probably remember my Photoelectric emission problem ...
> 
> My geometry consists of two concentric cylinders inside of a sphere
> (i.e. geometrically is axialsymmetric) .. the BC however, are NOT
> axialsymmetric and depend on the colatitude angle:
> 	* which type of Jacobian should I use? If I understood correctly, I
> have a geometry in gmsh, I apply the normal Laplacian(phi) = 0 and by
> using Jacobian, any Riemann geometry can be solved, am I right? could
> you comment a little on this please?
> 	* for those Neumann BC on he surface of the outer sphere I need to
> define a function that depends on the point of the boundary in which we
> are and the value of phi (the exponential of the value of the potential
> at that point and the coltitude at that point), how can I do that? I
> mean to recover the value of the position of the node that it is being
> used in that moment? because it is better to use nodes here isn't it? (I
> mean for the FunctionSpace ..). How can I include the value of what I am
> going to solve into the function?
> 
> Many thanks and sorry for bothering you with probably stupid questions
> ..
> 
> Nacho