Re: [ff3d-users] Modification of the domain during run time

[Stephane Del Pino]

Emilio Melero García wrote:
> Hi everyone!!
>
> I have a question to all of you see if any of you can help me. I am 
> concerned with a problem in which the volumes defining my domain should 
> change with time (trying to model very simplistic crystal nucleation and 
> growth). Any suggestion of how can i try it with ff3d? do you know of 
> any other free FEM code that would allow this?
Hello.

A short answer is yes. However a better description of the problem that 
you want to solve would help.
1) If you have a tetrahedrized mesh of your problem, you can use the 
'transform' keyword to compute a new mesh and then solve your equation 
with it : if 'm' is a (tetrahedrized) mesh
        m = tetrahedrize([f1,f2,f3],m);
will use the field [f1,f2,f3] to move the nodes of the mesh 'm' and will 
store it in a new version of 'm'

2) if you want to use fictitious domain method, it is implemented only 
if you use an analytic description of the domain (not POVRay) :

for instance for a sphere centered in 0 and of radius 1

        domain d; // domain is undefined here
        function ki = one(sqrt(x^2+y^2+z^2));
        d = domain(ki>0.5);

then solve your PDE using the domain 'd'.
Then if you can compute a new 'ki' you can redefine the domain in a loop 
for instance.

The modification of a povray file is not possible up to now but it will 
be implemented in the future.

I hope that helps.

Best regards,
Stephane.