Subject: Re: [FFC-dev] [DOLFIN-dev] Electromagnetic FEM

From: Bartosz Sawicki <[email-masked]>
Date: Thu, 27 Mar 2008 09:26:26 +0100

Lezar, Evan, Mr <[email-masked]>:
> Hi all
> 
> I have recently come across Fenics in my search for a finite element
> library to use in my PhD research.  I am involved in computational
> electromagnetics and typically use tangentially continuous edge, face
> and volume based vector basis functions to solve Maxwell's equations.
> These are higher order Nedelec basis functions. 
> 
> At the moment I am trying to come to terms with what is going on the in
> the code base and thought a good start would be to implement a solver
> for a simple 2D waveguide eigenvalue problem (The source-free vector
> Helmholtz equation). 
> 
> Is there anyone that has tackled something similar, or can give me a
> couple of pointers to get going?
> 

I'm solving ELF eddy currents problem with electric vector potential, 
where Nedelec elements are also used. In my problem electric and 
magnetic field can be separeted, but similary to you I also need 
tangentially continous elements.

Nedelec elements in Fenics just works (since February 2008), thanks to 
development by Marie Rognes :) Ensure that you use the most current 
version (my recommendation is version from repository).

Here you have one of my forms:
eN = FiniteElement("Nedelec", "tetrahedron", 0)
eL = VectorElement("Lagrange","tetrahedron", 1)
v = TestFunction(eN)
t = TrialFunction(eN)
dBdt = Function(eL)
mat = Constant("tetrahedron")
a= (1/mat)*dot(rot(v), rot(t))*dx
L = -dot(v,dBdt)*dx

regrd.
BArtosz