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Functional of Energy calculation

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Sorry for my simple question, because I'm a new in COMSOL. I would like to get a sequence of meshes for some elliptic boundary problem, say, for the Poisson problem with Diriechlet conditions, and a sequence of functionals of energy for each mesh. I'm interested in investigation of increasing of the values of functional under refining mesh.

4 Replies Last Post Nov 23, 2011, 3:37 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Nov 23, 2011, 2:38 a.m. EST
Hi

you can use a parameter for the mesh density, in most fields in the GUI you can use variables, not only constants

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Good luck
Ivar
Hi you can use a parameter for the mesh density, in most fields in the GUI you can use variables, not only constants -- Good luck Ivar

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Posted: 1 decade ago Nov 23, 2011, 2:48 a.m. EST
Thank you, Ivar. I understand the way of using parametric meshes, but I wonder, if the calculation of the functional of energy is an embedded function of COMSOL or it should be entered by some programming?
Thank you, Ivar. I understand the way of using parametric meshes, but I wonder, if the calculation of the functional of energy is an embedded function of COMSOL or it should be entered by some programming?

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Nov 23, 2011, 3:12 a.m. EST
Hi

I believe, if you work in pure "math" PDE mode that you must write out your equations yourself, by integrating over your domain but why should that be an issue ?

In most "physics" pre-cooked situations, you have numerous internal variables you might choose from, or make your own, as needed

But now I'm not 100% sure I fully understand what you are after ...

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Good luck
Ivar
Hi I believe, if you work in pure "math" PDE mode that you must write out your equations yourself, by integrating over your domain but why should that be an issue ? In most "physics" pre-cooked situations, you have numerous internal variables you might choose from, or make your own, as needed But now I'm not 100% sure I fully understand what you are after ... -- Good luck Ivar

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Posted: 1 decade ago Nov 23, 2011, 3:37 a.m. EST
Ok, I see from your answer, that I should calculate a functional as an integral over the domain and this integration is not an embedded function of COMSOL. I think, you understood me correctly. Thanks.
Ok, I see from your answer, that I should calculate a functional as an integral over the domain and this integration is not an embedded function of COMSOL. I think, you understood me correctly. Thanks.

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