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Solver dependency

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Hi,

I'm currently doing a simulation that involves free convection and I've read everything I could find on this forum about the subject. Something important that comes out, is that the solver that should be used is the "fully coupled" one. My solution is however converging with a "segregated" solver, but not with this fully coupled one. My question is the following : Can I trust my results independently of the solver (seeing that when I refine the mesh, the results are pretty much the same) ?

Thank you for the help. Best regards,
Pascal

1 Reply Last Post 2012/08/11 3:23 GMT-4
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2012/08/11 3:23 GMT-4
Hi

the difference is mainly in the speed and RAM use, a segregated solver usually uses less RAM but takes longer, while a Direct solver usually uses more RAM but can be faster.

Try it out: select the solver node (just above the segregated solver node) and add a direct solver node (right click), that will disable the segregated one, and resolve, and compare the results

If you do this in a new study sequence you can compare the two results and not overwrite ;)

--
Good luck
Ivar
Hi the difference is mainly in the speed and RAM use, a segregated solver usually uses less RAM but takes longer, while a Direct solver usually uses more RAM but can be faster. Try it out: select the solver node (just above the segregated solver node) and add a direct solver node (right click), that will disable the segregated one, and resolve, and compare the results If you do this in a new study sequence you can compare the two results and not overwrite ;) -- Good luck Ivar

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