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Re: KSP/PC choice
Dear Lisandro,
On Mon, 23 Jul 2007, Lisandro Dalcin wrote:
On 7/23/07, Tim Kröger <tim@xxxxxxxxxxxxxxxxxxx> wrote:
> What kind of stabilization for advection and pressure are you using?
Streamline diffusion (for advection). I am not aware of the
requirement to stabilize the pressure as well.
Well, you need to stabilize pressure if you have a non div-stable
finite element space (this happens when using linear, equal-order FE
for both velocity and pressure). Surely you are using a stable FE.
I'm using Taylor-Hood tetrahedron elements.
I'm not exactly sure what do you understand for 'streamline difussion'
(is rathre general). But we normally use non div-stable FE pairs,
formulated with SUPG/PSPG (the first for advection, the second for
pressure) stabilization, as proposed by Tezduyar in many publications.
I think it's the same that I am using, but I am not sure. Can you
give me a helpful reference?
If you are interested in trying the my solution, I can help you. But I
cannot assert you will have good performance, specially in big 3D
problems. Anyway, we are currently using it to simulate the flow
around a racing car (Re=16e6) with about 600K nodes in 30 processors.
I'm currently trying Matt's suggestion (to use MUMPS). (It seems not
to easy to install MUMPS.) Anyway, I would like to try your solution
as well. What would I have to do?
Best Regards,
Tim
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