Re: [ff3d-users] Basic Question on Fictitious Domain method

[Stephane Del Pino]

Hello.

Le lundi 21 décembre 2009, Juzar Thingna a écrit :
> Hello Everyone,
> I'm quite new to the fictitious domain method of solving PDE. I wanted to
> know how is this method better than the Finite element method? 
It is not better. FDM relies usually on finite element method.

> while doing
> some basic research one advantage I see is that the number of iterations
>  for convergence in CG is quite small in complex geometries because of the
>  pre-conditioner used.
This can be the case for some methods but in ff3d, FDM are used to avoid the 
complexity of 3D mesh generation. It is not a performance issue.

>  But I'm still not able to figure out how the
>  geometry can make the matrix ill-conditioned?
You should have a look to finite element method analysis.

Best regards,
S.