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coarse mesh converges but fine mesh does not

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Hi,

I have a model file that converges with a coarse mesh but it does not converge with a fine mesh. I am solving a stationary flow problem with FSI. I have tried several things like changing solvers from iterative to direct, using the coarse mesh solution to solve the fine mesh problem but I have had not success.

Anybody had any problems like this? Please let me know if you have any ideas that will help me resolve this.

Thanks,
Sirisha

1 Reply Last Post 2011年8月22日 GMT-4 01:45
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 2011年8月22日 GMT-4 01:45
Hi

have you done your validation and verification fully , as for FSi its rather important, for the fluidics, you need to ensure your flow regime is compatible with the initial conditions, to converge to something "correct", that your mesh is compatible with all dependent variable gradients, but also flow parameters such as the Raynolds number. The same for the structural.

coarse mesh does not necessarily mean wrong results, just as converging results does not necessarily mean correct results

all this is really very model and material parameter dependent, I find it difficult to define a "the correct check list" for FSI

--
Good luck
Ivar
Hi have you done your validation and verification fully , as for FSi its rather important, for the fluidics, you need to ensure your flow regime is compatible with the initial conditions, to converge to something "correct", that your mesh is compatible with all dependent variable gradients, but also flow parameters such as the Raynolds number. The same for the structural. coarse mesh does not necessarily mean wrong results, just as converging results does not necessarily mean correct results all this is really very model and material parameter dependent, I find it difficult to define a "the correct check list" for FSI -- Good luck Ivar

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