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Error with finer meshes

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Dear,

My program which is about the solution of some diffusion and reaction equations in a cube works very well for coarser and extra coarser meshes, however when I repeat the analyse with finer meshes, the program does not converge after a certain time step. And still gives good results up to that point. Can you please help me to understand the reason of this. Thanks in advance.

1 Reply Last Post Oct 12, 2016, 10:57 a.m. EDT

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Posted: 8 years ago Oct 12, 2016, 10:57 a.m. EDT
Hi there,

If nothing else has changed within the model other than the mesh density, then it may well be a memory limitation on the machine you are running the simulation on.

Presumably you can justify the need to increase mesh density by studying the results from the models with coarser meshes? Is the solution accuracy not quite good enough with the coarser meshes?

I know that sometimes the discretisation settings and method of result recovery can be experimented with in order to improve the result accuracy, negating the need to cram more elements into the model.

Aside from these general suggestions, you may need to dig into the solver settings for the particular Physics that you are dealing with, (I'm afraid I can't help with that though)!

Hope you manage to get a solution!

Mark
Hi there, If nothing else has changed within the model other than the mesh density, then it may well be a memory limitation on the machine you are running the simulation on. Presumably you can justify the need to increase mesh density by studying the results from the models with coarser meshes? Is the solution accuracy not quite good enough with the coarser meshes? I know that sometimes the discretisation settings and method of result recovery can be experimented with in order to improve the result accuracy, negating the need to cram more elements into the model. Aside from these general suggestions, you may need to dig into the solver settings for the particular Physics that you are dealing with, (I'm afraid I can't help with that though)! Hope you manage to get a solution! Mark

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