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Carola August 21, 2003 08:26

Help me Robin!
One more time Robin!, I got a couple of questions to you: 1)What do you mean when you say:"... An error correction is solved on each of the coarser grids and passed back up to the finer grids to improve the solution..", I understood like with every iteration the error is reduced until it reach the tolerance value..., Im wrong?.Where this error correction come from?.

2)What is the diference between time step and iteration?.

Sorry if I made a lot of stupid questions but I finally found someone who can explain to me this kind of things in a very simple way !

Take Care,


Robin August 25, 2003 16:55

Re: Help me Robin!
Hi Carola,

The error correction is just a detail of the additive corrective multigrid method and occurs within a single iteration/timestep.

Iteration and timestep are often used interchangably. CFX-5 and CFX-TASCflow include transient terms in the equations and each "iteration" of the solver in a steady state run is also a "timestep". If you run a transient simulation, a single timestep may include multiple iterations, usually referred to a inner coefficient loops.

Hope this helps.

Regards, Robin

Carola August 27, 2003 13:33

Thanks Robin!

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